THE PROSPECTS OF PLASMATRON ON-BOARD FUEL REFORMING
VEHICLES
By
Joseph Matthew Mensching
Bachelor of Science, Mechanical Engineering
Worcester Polytechnic Institute, 1998
Submitted to the Department of Mechanical Engineering in Partial Fulfillment of the
Requirements for the Degree of
Master of Science in Mechanical Engineering at the
Massachusetts Institute of Technology
USScTh T ITITUTE
OF TECHNOLOGY
September 2002
(D2002 Joseph M. Mensching. All rights reserved.
The author herby grants to MIT permission to reproduce and to distribute publicly paper and electronic copies of this thesis in whole or in part.
A
Signature of Author ph M Mensching gust 9, 2002
I
Certified by
John B. Heywood
Sun Jae Professor of Mechanical Engineering
Thesis Advisor
Accepted By
_ _ __*_
Ain A. Sonin
Professor, Department of Mechanical Engineering
Chairman, Department Graduate Committee

2

THE PROSPECTS OF PLASMATRON ON-BOARD FUEL REFORMING
VEHICLES
By
Joseph M Mensching
Submitted to the Department of Mechanical Engineering of Massachusetts Institute of
Technology on August 9, 2002 in partial fulfillment of the requirements for the Degree of
Masters of Science in Mechanical Engineering
ABSTRACT
Improvements in fuel economy and emissions are on-going areas of development in the automotive industry. The reasons for this are economic from the standpoint of the end user and consumer, and forced
by Government regulations instituted for political reasons as well as foreign Policy. The two main areas of research are new propulsion system concepts such as electric's, hybrids, and fuel cells; and improvements to conventional engine technology. The author has examined many of these new propulsion system concepts and found that they all share technical promise, but lack competitive economics to the conventional internal combustion engine. Given that current gasoline internal combustion engines only transform 20 to 30 percent of the chemical energy in fuel to useful propulsion energy, there is a far more realistic opportunity to realize substantial gains with advancing this existing technology.
Conventional spark ignition (SI) engines spend most of their time operating at a throttled condition for part power operation while losing significant energy to simply pumping air into the cylinders. Engine designers would like to obtain the benefits from simply metering the fuel flow into the engine rather than the airflow
(as in diesel engines) which eliminates these pumping losses. The current issue with diesel engines for light duty vehicles is the additional cost, and particulate & NOx emissions. The main reason why an SI engine cannot run in these lean (caused by reduced throttling of air, while instead controlling fuel flow) conditions is the reduced flame speed stability. One way that has proven to increase the lean limit of combustion is hydrogen addition.
In addition to reducing throttling losses, lean operation results in improved indicated fuel conversion efficiency (efficiency of the compression and combustion strokes only)
This research has developed a preliminary model of life cycle cost benefits of an on-board fuel reforming device (a plasmatron), which creates a supply of Hydrogen from a fuel-air mixture. Several plasmatron engine system configurations are evaluated including lean, higher compression ratio, and turbo charged plasmatron engines. The turbo charged plasmatron engines, which allow the overall engine displacement to be reduced, provide the highest possible improvements in Specific Fuel Consumption (SFC), but are currently in need of additional feasibility testing. The SFC improvements obtainable with the plasmatron are of a potentially high economic and practical attractiveness when compared to hybrid, fuel cell, and conventional vehicles.
Advised by: Professor John B. Heywood, Sun Jae Professor qf Mechanical
Engineering
3

4

ACKNOWLEDGEMENTS
I would like to acknowledge my colleagues at the MIT Sloan lab; Ed Tully, Jennifer
Topinka, and Rudy Smalling, and my advisor; Professor John Heywood who have contributed their research, experience, and ideas to this thesis.
I would like to acknowledge the shareholders and associates of General Electric
Corporation, for their financial support of my Masters degree at MIT and my career for the last 5 years.
Finally, I would like to acknowledge my parents, Eugene F. Mensching, and Christine
Simpson, for their financial support for my undergraduate studies at Worcester
Polytechnic Institute, as well as their unconditional approval and support of all my educational, professional, and personal endeavors.
I encourage all to consider the importance of our freedom of mobility in this country and the globe to our lives and our economy. All the scientists and engineers working on the advancements of vehicles and propulsion systems around the world are helping to preserve our mobility, and our freedom.
Joseph M. Mensching, 2002
5

6

TABLE OF CONTENTS
ABSTRACT........................................................................................................................ 3
ACKNOW LEDGEM ENTS............................................................................................
1.3 Purpose of study......................................................................................................
5
TABLE OF CONTENTS................................................................................................. 7
LIST OF TABLES .......................................................................................................
LIST OF FIGURES ....................................................................................................... 10
NOM ENCLATURE ......................................................................................................... 11
CHAPTER I: INTRODUCTION ................................................................................. 13
1.1 Background................................................................................................................
1.2 The Plasmatron; W hat is it? W hat are the benefits?........................
13
.... .............. ... . .
13
9
15
1.4 Description of the model........................................................................................
CHAPTER II: FUEL PRICE M ODEL ........................................................................
16
17
CHAPTER III: ADVISOR CODE............................................................................... 21
3.1 Purpose of the code / How the code works............................................................. 21
3 .2 V eh icles...................................................................................................................... 24
3.3 Drive cycles ............................................................................................................... 25
3 .4 R e su lts ........................................................................................................................
CHAPTER IV: PLASM ATRON ENGINE M ODEL..................................................
4.3 Chemical efficiency of the plasmatron ...................................................................
2 7
31
4.1 Indicated fuel conversion efficiency improvem ent................................................ 31
4.2 Brake fuel conversion efficiency ............................................................................ 38
39
4.4 Electrical Energy requirements............................................................................... 40
4.5 The effects of friction............................................................................................. 42
CHAPTER V: LIFE CYCLE COST M ODEL ............................................................ 45
CHAPTER VI: DISCUSSION OF RESULTS ............................................................ 49
6.1 Case 1. Naturally Aspirated Engine; Compression Ratio of 10............................ 49
6.2 Case 2. Naturally Aspirated Compression Ratio of 14 .......................................... 53
6.3 Case 3. Turbocharged Engine; Compression Ratio of 14...................................... 55
6.4 Case 4. Reduced engine size facilitated by Plasmatron and more Boost.............. 58
6.5 Case 5. Sensitivity analysis and further potential gains........................................ 60
7

6.6 Case 6. "Transition Engine" .................................................................................
CHAPTER VII: LIMITATIONS......................................................................................
CHAPTER VIII: CONCLUSIONS ..................................................................................
Appendix A List of Assumptions and Selected Results ..................................................
Appendix B. 1 Baseline Engine SFC.............................................................................
Appendix B.2
Case 1. Plasmatron, N.A., rc=l0 Engine SFC ..........................................
Appendix B.3
Case 2. Plasmatron, N.A., r,=14 Engine SFC .........................................
Appendix B.4
Case 3. Plasmatron, Turbo (0.5 atm Boost), r,=14 Engine ..............
Appendix B.5 Case 4. 1 atm Boost, reduced engine size (2.2L) ....................
Appendix B.6
Case 5. Im provem ent Sensitivities ...........................................................
Appendix C.1 Plasmatron Model Assumption Group b...................................................
Appendix C.2 Plasmatron Model Assumption Group c ...................................................
Appendix C.3 Plasmatron Model Assumption Group d ...................................................
Appendix C.4
Plasmatron Model Assumption Group e ...................................................
Appendix C.5 Plasmatron Model Assumption Group f....................................................
Appendix C.6 Plasmatron Model Assumption Group g ...................................................
Appendix C.7 Plasmatron Model Assumption Group h ...................................................
Appendix C.8 Plasmatron Model Assumption Group I.................................................... 93
Appendix C.9 Plasmatron Model Assumption Group j................................................ 94
Appendix C. 10 Plasmatron Model Assumption Group k ............................................. 95
85
87
89
90
91
92
80
83
78
79
73
75
76
77
63
67
69
8

LIST OF TABLES
Table 3.1 Analysis Vehicle Specifications ...................................................................
25
Table 4.1 Electrical MEP (kPa) At the Engine Crankshaft ..........................................
Table 4.2 Simplified Electrical MEP (kPa) Versus Load Only....................................
Table 4.3 Example of Friction MEP Versus Speed ......................................................
Table 4.4 Nominal Error (% SFC Reduction) Constant Friction of 100 kPa versus m fM E P in T able 4.3......................................................................................................
41
41
42
43
Table 6.1 Case 1. Large Car Plasmatron MPG and Fuel Consumption Results........... 50
Table 6.2 Case 1. Large Car Fuel Savings Net Present Value Results.........................
51
Table 6.3 Case 1. Small Car Plasmatron MPG and Fuel Consumption Results........... 51
Table 6.4 Case 1. Small Car Fuel Savings Net Present Value Results......................... 51
Table 6.5 Case 2. Large Car Plasmatron MPG and Fuel Consumption Results........... 54
Table 6.6 Case 2. Large Car Fuel Savings Net Present Value Results........................ 55
Table 6.7 Case 2. Small Car Plasmatron MPG and Fuel Consumption Results........... 55
Table 6.8 Case 2. Small Car Fuel Savings Net Present Value Results.........................
55
Table 6.9 Turbo Param eters ..........................................................................................
56
Table 6.10 Case 3. Large Car Plasmatron MPG and Fuel Consumption Results........ 57
Table 6.11 Case 3. Large Car Fuel Savings Net Present Value Results...................... 57
Table 6.12 Case 3. Small Car Plasmatron MPG and Fuel Consumption Results........ 57
Table 6.13 Case 3. Small Car Fuel Savings Net Present Value Results...................... 58
Table 6.14 Average M PG vs Boost & Engine Size ...................................................... 60
Table 6.15 Case 6. Large Car Plasmatron MPG and Fuel Consumption Results......... 65
Table 6.16 Case 6. Large Car Fuel Savings Net Present Value Results...................... 66
Table 8.1 Feasibility Score Table ................................................................................ 70
9

LIST OF FIGURES
Figure 1. 1 Diagram of Plasm atron Device ................................................................... 15
Figure 2.1 Historical US Fuel Prices (Sales weighted Average) Versus CPI............... 18
Figure 2.2 US Department of Energy Annual Energy Outlook (Automotive Fuel
C o st/B tu ) .................................................................................................................... 19
Figure 3.1 ADVISOR Block Diagram for a Conventional Automobile....................... 23
Figure 3.2 FTP (Urban) Driving Cycle......................................................................... 26
Figure 3.3 HW FET Driving Cycle................................................................................
Figure 3.4 U S0 6 D riving Cycle ...................................................................................
Figure 3.5 US06 Small Car Engine Mission................................................................
Figure 3.6 FTP Sm all Car Engine M ission....................................................................
Figure 3.7 HWFET Small Car Engine Mission............................................................. 29
Figure 3.8 US06 Large Car Engine Mission............................................................... 29
Figure 3.9 FTP Large Car Engine Mission....................................................................
Figure 3.10 HWFET Large Car Engine Mission...........................................................
30
30
Figure 4.1 Fuel A ir Cycle Results [3]...........................................................................
Figure 4.2 N O x Em issions versus k .............................................................................
33
35
26
27
28
28
Figure 4.3 SFC Reduction vs % Plasmatron Gas and k ............................................... 37
Figure 4.4 Summary of Net Plasmatron Benefits ........................................................ 43
Figure 6.1 Brake Fuel Conversion Efficiency Versus Load & % SFC Reduction..... 50
Figure 6.2 Case 2. Brake Fuel Conversion Efficiency Versus Load & % SFC Reduction w ith rc= 14 ................................................................................................................... 5 3
Figure 6.3 Case 3. Brake Fuel Conversion Efficiency Versus Load & % SFC Reduction w ith rc= 14 and T urbo .............................................................................................. 57
Figure 6.4 Reduced Engine Size SFC Reduction vs Load (Large Car)........................ 59
Figure 6.5 5-Year NPV vs Boost and Engine size........................................................ 60
Figure 6.6 Potential Improvements to SFR Reduction vs Load (Large Car)................. 62
Figure 6.7 5-Year NPV of Potential Plasmatron Improvements ................................... 63
Figure 6.8 k vs load for "transition engine" ................................................................. 64
Figure 6.9 Case 6. Brake Fuel Conversion Efficiency Versus Load & % SFC Reduction with r,=12, 1.2<%<1.7, and 3.3L Displacement ...................................................... 65
10

BMEP
CPI
CR, rc
EMEP
FTP
HWFET
IMEP mfMEP
MPG
NPV
SFC
QHv
NOMENCLATURE
Brake Mean Effective Pressure (kPa)
Consumer Price Index
Compression ratio
Mean Effective Pressure attributed to the electrical demands of the plasmatron
Federal Test Procedure (Urban Driving Cycle)
Highway Fuel Economy Test (Highway Driving
Cycle)
Indicated Mean Effective Pressure (kPa)
Mechanical Friction Mean Effective Pressure (kPa)
Miles per gallon
Net Present Value
Specific Fuel Consumption (g/kWhr)
Heating Value (MJ/Kg)
Relative Air/Fuel Ratio
Relative Fuel/Air Ratio
11

12

CHAPTER I: INTRODUCTION
1.1 Background
As we are beginning to see hybrid vehicles enter the market place, and government support and recognition of fuel cell development, it is clear that a social and political if not economic as well, demand exists for new, reduced fuel consumption vehicle technologies.
The current hybrid vehicles cost far more to produce than their conventional vehicle counterparts, and the resulting fuel savings does not offset the vehicles cost over its lifespan. Currently, manufactures are not selling hybrids profitably, with hope that the costs will come down over time. Fundamentally, hybrid vehicles are more complicated than their conventional siblings with two drive systems needed; an electric, and a gasoline powerplant. In addition to this, two storage systems are needed; electrical energy storage and gasoline storage. For this reason, the author believes that obtaining manufacturing costs that can compete with conventional vehicles may be an insurmountable task.
Fuel cells promise to be the most dramatic reform in vehicle propulsion systems, however most experts in the field agree that we may be up to 20 years away from driving fuel cell powered vehicles on a wide spread basis. Fortunately, there are currently many other opportunities for advancing conventional internal combustion propulsion systems, which could become available in as little as 3-5 years. The plasmatron on-board fuel reforming system is one of these developments, and is the subject of this thesis.
1.2 The Plasmatron; What is it? What are the benefits?
The plasmaton device has been developed at the Plasma Science and Fusion Center at
Massachusetts Institute of Technology. For the purpose of the vehicle technology that is the subject of this thesis, the goal of the plasmatron is to reform a hydrocarbon fuel air mixture into a hydrogen enriched mixture. The chemical process is stimulated by an
13

electrical plasma arc inside the device as shown in Figure 1.1, which causes to fuel to partially oxidize. An example chemical reaction is
C
7
H
14
+3.5(02+3.773N
2
) = > 7CO +7H
2
+13.21N
2
.
We can see that the hydrocarbon is only partially oxidized, and the hydrogen is released.
In real operation, there will always be some complete oxidation, meaning that some portion of the reactants will form CO
2 and H
2
0. This results in an inefficiency in the plasmatron itself which should be minimized by design. The reaction is exothermic because a portion of the fuel energy is released, and there will be a significant heating of the mixture.
The benefits of using this device, is that the resulting hydrogen enriched gasoline-air mixture (only about 20% of the engine's total fuel-air mixture) will allow a leaner burn limit for the engine, a higher compression ratio, and hence reduced fuel consumption and emissions. The same result could be achieved through direct addition of hydrogen gas, however storage and infrastructure are the main obstacles. The plasmatron device enables hydrogen production from the same fuel source in which the engine is already operating and for which the infrastructure has existed for many decades.
On the surface, one may expect the level of increased fuel economy approaching that of a diesel engine which also runs lean and has an efficiency of~1.34 times that of a similar spark ignition engine. The most important aspect would be that this diesel-like performance would come without the emissions and noise problems associated with the diesel. In addition to these issues, the diesel is currently economically attractive predominantly to operators with high vehicle utilization or high fuel costs; either of which is required to justify the additional expense of the diesel engine system. The plasmatron vehicle would not need the complicated high pressure fuel injection system of the diesel, nor the sophisticated after treatments needed to keep emissions in check, so its costs might very well allow for economic feasibility in a much broader market.
14

Hydrogen Enriched
Mixture to engine
Reaction
Extension
Cylinder
Arc
Discharge
Ground
Air-Fuel Mixture
Electrode
Figure 1.1 Diagram of Plasmatron Device
1.3 Purpose of study
The purpose of this study is to create and utilize a modeling approach that will take into account the various plasmatron system efficiencies, the probable degrees of lean engine operation, and increased compression ratio to evaluate the economic value and feasibility of the system. The model must translate the technical parameters into dollars. This requires a complete system analysis that includes the plasmatron, the engine, the vehicle, the type of vehicle operation, and fuel costs over a representative period of time.
15

This study will act as an aid to further develop the plasmatron system by quantifying the end effects of system design parameters and configurations, and will help to identify design goals and shortcomings which require attention and further development.
1.4 Description of the model
The purpose of the model is to translate various degrees of design success into a dollar value. Specifically, if we achieve some level of lean operation at the cost of some amount of plasmatron gas produced with some other level of efficiency; what are the economics of the system? The model must account for the powertrain, the vehicle, the method of operation, fuel prices, and the payback period or life of the vehicle. The ultimate use for the model in this study is to predict the final performance of plasmatron vehicles rather than develop or optimize the specific design.
The approach will consist of several sub-models or sub-analyses. They are as follows:
The vehicle model (which is based on the ADVISOR code) simulates the vehicle dynamics and translates the required vehicle motions into the specific operating demands on the engine. The plasmatron and engine models attempt to predict the performance of the plasmatron engine system relative to a conventional engine system. The fuel cost model simply attempts to predict real fuel prices over time based on historical trends and industry predictions. Finally, the life cycle cost model merges the data from the other models to calculate fuel expenditures on an annual basis.
16

CHAPTER 11: FUEL PRICE MODEL
To assess the value of a technology of which the primary benefit is fuel savings, it is reasonable to translate the fuel savings itself into a nominal dollar amount. To do this, it is necessary to look at fuel prices and make an estimate of fuel prices well into the future.
The cost of fuel will play a crucial role in what vehicle technologies are marketable. One example of this is the use of diesel engines in light duty vehicles in Europe versus the
United States. In Europe, where fuel costs often exceed two times of that of the US, more expensive diesel powered cars are much more common and marketable. There must be then, an equation involving the cost of the fuel, the incremental vehicle cost, the fuel savings, and the total vehicle utilization that will determine the marketability of an improved fuel efficiency technology.
To analyze the plasmatron feasibility in the US market, US fuel prices should be used; however, to extrapolate to other markets, we could simply scale to fuel savings value by the relative difference in fuel prices as an approximation. For example, if it is determined that the plasmatron technology might represent $700 USD of real fuel savings value to the US operator, we could make the assumption that, in a region where fuel prices tend to be double that of the US, then the value of the technology might also be doubled, all other things being equal; i.e. $1400 USD.
17

a
D
61%
1.6
1.4
1.2
0.8
1
-
--
-- -+-CPl
-- Fuel Price delta %X
0.6
0.4
0.2
0
I I
1960 1970
I
1980
I
1990 20 C 0
100%
80%
60%
40%
20%
0%
-20%
-40%
Figure 2.1 Historical US Fuel Prices (Sales weighted Average) Versus CPI
As shown in Figure 2.1, the overall nominal price of gasoline has followed the consumer price index (CPI), but with some periods of significant variation. Most notably, the energy crisis of the late 70s resulted in a period of high prices. Since so many external factors will affect future fuel prices such as politics, conflicts in other oil producing nations, and future demand spikes or declines based on economic cycles, it is difficult to develop a logical model to predict prices over the next 10 to 20 years.
The United States Energy Information Administration publishes an energy outlook with projections to the year 2020 [1]. This report indexes the sales weighted average annual gasoline prices including state and local taxes in real dollars (i.e. adjusted for inflation /
CPI). We can see from Figure 2.2, that the projection is basically flat with CPI over the next 18 years.
18

US DOE Annual Energy Outlook
0
E6
8
12-
10-
2 -
-
2002 2004 2006 2008 2010 2012 2014 2016 2018 2020
Figure 2.2 US Department of Energy Annual Energy Outlook (Automotive Fuel
Cost/Btu)
As stated earlier, the basis for evaluating a given fuel efficiency improvement technology will be its fuel savings over time, or in a slightly more sophisticated way, the net present value of the fuel savings. The research into fuel prices indicates that fuel prices, over the long run, will basically follow the CPI, and that in any shorter term, large variations are possible due to world events.
If we were to say that one would expect some nominal rate of return on an investment, say 10%, and that as part of that, one would also expect inflation to be 4% year over year, implicitly, one is really expecting a 6% return on their investment in real terms. This being said, if fuel prices are expected to follow inflation over the long run, and one is expecting a 6% return in real dollars, then the savings model becomes very simple. The actual inflation that occurs, as measured by the CPI, is not really important as long as we assume that one would demand a 6% return above this amount. As long as fuel prices do in fact follow CPI in the long run, the real net present value of a given annual fuel savings, with a given life cycle, is a simple calculation.
19

20

CHAPTER III: ADVISOR CODE
3.1 Purpose of the code / How the code works
ADVISOR (Advanced VehIcle SimulatOR) is a code that has been produced and made readily available by the Center for Transportation Technologies and Systems of the
National Renewable Energies Laboratory. The code was developed for modeling complete vehicle system concepts, and especially hybrid vehicles, beginning with the driving pattern which includes accelerations, decelerations, inclines, declines, etc. to the vehicle driveline including tires, suspension, drive axle, transmission, etc. to the engine.
The output of the code includes emissions, fuel consumption and vehicle performance.
The ADVISOR code runs in Matlab Simulink, and is easy to customize and modify.
Although ADVISOR has been designed to handle hybrid vehicle system designs, it can just as easily analyze a conventional powertrain. The major shortcoming with ADVISOR for this study is that ADVISOR simulates a vehicle system, and assumes that the individual components are already well defined. For the plasmatron, it is desired to retain a common vehicle configuration, namely, something identical to a conventional vehicle, while making modifications to the vehicle powerplant only.
In evaluating the plasmatron system itself, for simplification purposes, it is desirable to assume a design goal of identical torque-speed performance to that of the conventional engine. This being established, the ADVISOR code can be used to generate the necessary loads at the engine output shaft that would be present with or without the plasmatron while taking into account the drive cycle and vehicle dynamics. The other features of ADVISOR are not used as an excel model was created to model the engine and fuel consumption economics. Alternatively, the ADVISOR code could be modified to include an engine and financial model rather than creating the excel model, however as a personal choice, excel has been chosen for this. The reason, is that the author feels that as the model is intended to be more of a financial and economic model than an
21

engineering one; excel tends to be more widely used by the finance and business community, whereas Matlab is known as more of an engineering tool.
A short overview of the code and how it works as it pertains to its usage in this study is prudent; however, this is not intended to be a "manual" for the ADVISOR program, nor does it even begin to cover all of the applications and features of the program.
To begin, the inputs to the program consist of several data files and a user interface. The data files consist of component definitions and performance specifications, and the user interface allows one the choice which component data files will be used to model different components and how the components will be configured. For a conventional vehicle, the vehicle configuration is relatively standard. In addition to the components, and input file exists for the vehicle's "mission" or "drive cycle" which basically contains the speed versus time trajectory.
The data input files consist of:
Drive Cycle: This file consists of a table of speed and elevation versus time.
Fuel Converter: The fuel converter file has various tables indexed by torque and speed with data on specific fuel consumption and emissions. It also contains the maximum torque versus speed for the engine and the provision for a temperature correction factor.
Exhaust: The exhaust file basically consists of the catalyst efficiencies and catalyst limits.
Transmission: This data file contains the gear ratios, shift points, coasting properties, and losses.
Vehicle: The vehicle file contains the physical specs of the vehicle itself; weight, rolling resistance, drag coefficient, frontal area, etc.
Wheel and axle: Contains the wheel and axle losses, rolling inertia, diameter, etc..
Accessory: This file simply contains the accessory mechanical loads on the engine.
22

The basic calculation sequence is shown in Figure 3.1. The code begins with the drive cycle and works through the vehicle dynamics to determine the torque and speed output required by the engine at every step in time. This is seemingly a backward approach as the simulation is driven by the required speed and acceleration of the vehicle rather than
by the engine. There is however a feedback which checks the engines ability to produce the torque that is demanded resulting in some discrepancy between the drive cycle and the actual drive cycle that the vehicle follows. If the vehicle is designed appropriately for its mission, this discrepancy should be small.
drive cycle vehicle <veh>
(sdo> conv
<vc> con auto dbeM axle.....xh... converter <hto> total fuel used (gal) ex cal c
Altia off ex-cat tmnp
<cs>
Figure 3.1 ADVISOR Block Diagram for a Conventional Automobile
Once the actual delivered torque and speed of the engine is determined, the code basically looks up and interpolates between the points in the fuel converter file to calculate the fuel use in grams as well as the various emission products in grams.
The exhaust flow rate and temperature from the fuel converter are then used by the series of exhaust system thermal calculations to determine the system performance. The emissions are then adjusted for the exhaust system catalyst efficiencies to determine the final vehicle-out emissions.
The plasmatron system model requires the engine torque and speed versus time to calculate the system fuel use based on projected efficiencies. Since we have a desired drive cycle to analyze, the ADVISOR code can be used to simulate the vehicle dynamics
23

to translate the drive cycle into the engine crankshaft torque and speed cycle. Once these cycles are loaded into the plasmatron model, they can be essentially frozen, based on the assumption that the vehicle designs themselves are frozen, and that the discrepancies between the required and available engine torque will always be small.
3.2 Vehicles
Given that the plasmatron tests to date have been on engines that are basically used for light duty passenger vehicles, and that this is potentially the largest market for the plasmatron since larger trucks almost exclusively use diesel engines, this may be the best
"ballpark" to consider for modeling the plasmatron. It may also be of value to consider both a small vehicle, such as an economy car, or a vehicle about the size of the current hybrids, and a larger car that is more representative of the average vehicle that Americans drive.
The advisor code is made available with pre-written input files for various vehicles or alternatively, one can make their own input files. Since a specific test vehicle has not been identified at the current time, it is not worth creating a customized set of data for the plasmatron vehicle. Rather, we can utilize the readily available sets of vehicle data that has already been written for advisor. Intuitively, it might be easier to market the plasmatron on a larger vehicle where the total fuel expenditures are higher resulting in a higher nominal monetary fuel cost savings, and where the margins are not a slim as economy cars such that adding some cost for the plasmatron device will be more feasible.
On the other hand, purchasers of small economy vehicles may be a more fuel efficiency conscious consumer than the purchaser of a larger or more luxury vehicle. Table 3.1 shows the vehicles analyzed.
24

Table 3.1 Analysis Vehicle Specifications small car weight 2582 Ibs (1171 Kg) frontal area drag coeff
2.0 mA2
0.335 engine Saturn 1.9L max power 95 kW @ 6000 RPM max torque 165.36 Nm large car
3532 Ibs (1602 Kg)
2.04 m^2
0.33
Dodge 3.0 L
102 kW @ 4875 RPM
214.2 Nm
3.3 Drive cycles
The driving cycles to be used in the simulations are listed and described below. The idea is to use the cycle that would be used by the EPA for emissions testing which is supposed to simulate normal driving. Given that studies have shown some driving to include much more severe accelerations which are included in the US06 cycle, it is advantageous to include this cycle as well.
FTP (Urban): This data represents the Federal Test Procedure uban driving cycle used
by the US EPA for emissions certification of passenger vehicles in the US. (from the
EPA website) [9] See Figure 3.2.
EPA Highway: This data represents the Highway Fuel Economy Test (HWFET) driving cycle used by the US EPA for Corporate Average Fuel Economy (CAFE) certification of passenger vehicles in the US. See Figure 3.3.
USO6: This cycle is one of three included in the US EPA's Supplemental Federal Test
Procedure to be used to measure vehicular tailpipe emissions. The US06 includes high speed operation and demanding accelerations. See Figure 3.4.
25

CYCFTP
100 key on
elevation
(D
.1D
Qm
0 500 1000 time (sec)
1500
Figure 3.2 FTP (Urban) Driving Cycle
2000 2500
,I
(D
(D
0D
CYCHWFET
100 key on speed elevation
CDL
ED
50
-T
0 60
' '' '' \
0
I
0
I *1
100 200 300 400 500 600 700 800 time (sec)
Figure 3.3 HWFET Driving Cycle
26

100 key on speed elevation
CYCUS06
0I
E
50
4-j
(-
.4
0D
0 100
Figure 3.4 USO6 Driving Cycle
200 300
400
3.4 Results
500 6 00
The results of running the ADVISOR simulation which will be utilized the life cycle economics model consist of the engine crankshaft loads and speeds required for the various missions or drive cycles. These data points (each point representing a 1 second time step of operation) are shown in the figures 3.5, 3.6 & 3.7 that follow. The insight that we gain by looking at these charts is a look at the actual part of the engine's operational envelope that is actually being utilized during these drive cycles. This will give us some idea of how effective performance improvements may be that effect different parts of the engine's operational envelope.
27

USO6 Small Car Engine Crankshaft
200
150
100
0*
0
Iz
4) 50
0
-50
-100
3000
Speed (RPM)
Figure 3.5 USO6 Small Car Engine Mission
4000 5000 60
00
FTP Small Car Engine Crankshaft
200
150
E
100
50
0*
0
-50
-100
' g
L~ ****
-
3000
Speed (RPM)
Figure 3.6 FTP Small Car Engine Mission
4000 5000 6000
28

HWFET Small Car Engine Crankshaft
200
150
100z
0
50
0-
-50
-100
4P
* t h~ a
3000 4000
Speed (RPM)
Figure 3.7 HWFET Small Car Engine Mission
5000 6000
USO6 Large Car Engine Crankshaft z
4)
0*
I-
0
100
50
0
-50
-100
250
200
150
&... h . N
404
3000
Speed (RPM)
Figure 3.8 USO6 Large Car Engine Mission
4000 5000 60 00
29

FTP Large Car Engine Crankshaft
250
200
150 z
100 1
10
50
0
-50
-100
7,
* *
3000
Speed (RPM)
Figure 3.9 FTP Large Car Engine Mission
4000 5000 6000
HWFET Large Car Engine Crankshaft
250
200
150
E
100
0*
50
0
-50 i
-100
1 'V
* *
3000
Speed (RPM)
Figure 3.10 HWFET Large Car Engine Mission
4000 5000 6000
30

CHAPTER IV: PLASMATRON ENGINE MODEL
Now that the engine mission has been determined by the drive cycles and the vehicle dynamics through the ADVISOR code, in order estimate the real benefits of a plasmatron vehicle, we need to modify an existing fuel consumption map with the changes resulting from the plasmatron engine configuration. The approach is as follows: If the fuel consumption benefit can be established as a percent reduction across the torque-speed map for a "test engine", we can scale these results by normalizing on the percentage of maximum torque, the percentage of maximum speed, and the percent reduction in SFC.
This allows an approximate method to scale any given spark ignition engine performance map for the plasmatron.
The task of estimating the fuel conversion efficiency of a plasmatron engine against that of a baseline engine is most critical. Since the percentage of SFC reduction is critical, so to is the selection of the baseline. The baseline must be a current, but conventional spark ignition engine that can be modeled, then modified for the plasmatron, and modeled again. Some care must be taken in selecting the baseline; for example; we cannot compare an existing engine to a theoretical, and idealized plasmatron engine.
The steps for estimating the benefits of the plasmatron will be to attempt to book keep the indicated, or gross gains that we would expect fundamentally from a plasatron, and then do a realistic job of also book keeping the additional losses associated with the plasmatron over the engine torque-speed envelope.
4.1 Indicated fuel conversion efficiency improvement
The indicated fuel conversion efficiency, which can also be referred to as the gross efficiency can be described as the actual work done on the piston during the compression and expansion strokes divided by the theoretical maximum work. The theoretical maximum work assumes that all of the available chemical energy in the fuel is converted into work done on the piston. So, for example; the indicated fuel conversion efficiency
31

does not include engine friction, pumping losses during the intake and exhaust strokes, or accessory loads on the engine such as the water pump, oil pump, or alternator.
If one were to look at an ideal cycle analysis that assumes that the working fluid is an ideal gas, which goes through adiabatic compression, constant volume combustion
(basically, just heat addition), and adiabatic expansion, one would end up with for indicated fuel conversion efficiency.
The only variables in this expression are r, and 7. This is a highly idealized model, so many other variables, in reality, affect indicated fuel conversion efficiency; however these are the two most important fundamental parameters, for which, the plasmatron promises to have an effect on both.
The plasmatron provides a supply of hydrogen to the unburned fuel/air mixture entering the engine. Hydrogen addition has been shown to have positive effects on the combustion process, which should allow more flexibility with regard to the mixture in the
SI engine. With the improved combustion resulting from hydrogen addition, the lean limit of operation can be extended. Following from this, the more dilute (lean) mixture is expected to have higher knock resistance that will allow a higher compression ratio. In the ideal indicated efficiency equation above, the compression ratio is explicitly shown, and the y is a direct result the fuel air mixture, namely, a leaner mixture will have a higher 7.
As a quick note on compression ratio and knock limits; knock is a phenomenon that occurs due to the spontaneous, and rapid ignition of unburned end gas in the cylinder due to high temperatures partially caused by high peak cylinder pressure. The compression ratio in current SI engine technologies is limited by this knock phenomenon. Most SI
32

engines have compression ratios of around 10. Higher values usually require a premium, higher octane fuel.
A similar model to that described above, is the fuel-air cycle model. The fuel-air cycle model has the same basic assumptions as the ideal cycle model, except that the working fluid properties are more accurately accounted for. For example, the compressibility of the combustion products is different then that of the unburned fuel-air mixture, and thus the compressibility and specific heat properties are modeled (usually by means of gas tables). Figure 4.1 shows the results of fuel-air cycle analysis from [Heywood] for a typical 388K intake temperature and
5% residual gas mass fraction
Fuel Air Cycle Results (Heywood)
0.6
0.55
C.,
4)
C)
U.5
w
0
4)
4..
Cu
C.,
0.45
0.4
C
0.35
0.3
0.4
0.6
0.8 1
Rel. Fuel-Air Ratio
Figure 4.1 Fuel Air Cycle Results [3]
N
N
1.2
-CR=8
CR= 10
-- x- CR=12
3K
CR=14
-.- CR=16
1.4
---
The shortcomings that are still present with the fuel-air cycle model is that heat transfer are not accounted for, and the combustion process itself is not really modeled. This is
33

where more sophisticated computer codes come into play for modeling internal combustion engine performance, however, for our purposes, we are not interested in modeling the absolute engine performance, but rather estimating the gains that we will get from the plasmatron. This being said, there are aspects of the plasmatron engine combustion process which would require more sophisticated modeling, however, as a first pass, we might expect a reasonable estimate by comparing points on the fuel-air cycle chart for the indicated quantities.
Having some basic tools to estimate the indicated efficiency for a given fuel-air equivalence ratio $, or air-fuel equivalence ratio ), (k=1/$), and compression ratio, it is required to have some estimate of what the achievable air-fuel ratio and compression ratio might be. In this area, some experimental results and some logic might become an aid.
Ideally, as in a diesel engine, there would be no throttle, and the fuel-air ratio would become increasingly lean as the load is reduced. With the plasmatron engine, this might not occur for two reasons. One, there will be a lean limit that cannot be exceeded, albeit leaner than that of a conventional SI engine. Secondly, there may be increasing plasmatron gas requirements with ever increasing lean operation that will require additional electrical energy to produce as well as additional losses in the potential chemical energy of the gasoline fuel as a higher portion of it is converted through the plasmatron.
Based on these ideas, there may be three modes of plasmatron engine operation. Firstly, at light loads, the engine may be throttled while operating at the lean limit, or some predefined maximum air-fuel ratio. Secondly, at medium loads, the air-fuel ratio will be varied as necessary to match the load. Requirement. And, thirdly, there may be a minimum relative air-fuel equivalence ratio (>1) that will be allowed to maintain low
NOx emissions (See Figure 4.2), in which case the engine must jump to stochiometric (to allow use of a three-way catalyst) and be throttled, or, the engine remains lean and the extra power is obtained through turbocharging.
34

X
1.0 1.2 1.4 1.6 1.8
Figure 4.2 NOx Emissions versus X
To determine the lean limit of operation, an ideal experiment would be to run a test engine with several different levels of plasmatron gas and test for the lean limit of stable combustion. Analysis could then be performed that would calculate the overall system efficiency which would include the losses in the plamatron gas conversion. Ideally, there is a point where the increased levels of plasmatron gas (and also possibly decreased combustion stability) offset the incremental efficiency gains from running leaner than the previous level.
35

Some data relative to this experiment is available from engine testing completed at the
Sloan Automotive Lab at MIT [8]. The experiment demonstrates (roughly) a lean limit between k=1.6 to k=1.8 for 10 to 30% of the total fuel through the plasmatron. Since we would not want to run the engine much below k=1.7 due to the increase in NOx levels, and if we were to assume that k=1.8 would require an incremental 10% of additional total fuel through the plasmatron, we could calculate which point might be more ideal, and thus find the lean limit, or band of lean operation.
When running lean, the diluted mixture may allow a higher compression ratio to be achieved without the onset of knock. A diesel engine might have a compression ratio of
16 or above, which is substantially higher than its SI engine counterpart of around 10.
Since the plasmatron engine would still have an unburned fuel air mixture in the cylinder at high pressure, as opposed to a diesel in which the combustion is mixing controlled (no unburned mixture), compression ratios as high as the diesel engines may not be achievable. On the other hand, as the compression ratio is raised, the incremental benefit of increasing the compression ratio becomes smaller; therefore, a compression ratio of 14 achieves most of the benefit that would be obtained with a compression ratio of 16 or higher.
While experiments are currently being performed to test the possibility of increasing the compression ratio on lean burning plasmatron engines, assuming of a compression ratio of 14 will give a useful estimate of the potential benefits.
36

SFC
01
C
0
1C
U-
C/)
E
A
-+-
1.7
1.8
20%
Figure 4.3 SFC Reduction vs % Plasmatron Gas and X
As can be seen from Figure 4.3, an increase in X from 1.7 to 1.8 (going from point A to point B) does not offset the penalty due do increasing the % of fuel through the plasmatron (going from point B to point C). Therefore, this experiment might suggest that k=1.7 and 20% of the fuel through the plasmatron might be a good assumption.
These results however, are for a specific combustion system in a test engine, which does not discount the possibility that it may be possible to achieve higher X, such as %=2, without additional flow through the plasmatron being necessary. This might be achieved through other advancements in the combustion system.
37

4.2 Brake fuel conversion efficiency
Now that a method to estimate the relative benefit from the plasmatron on an indicated basis has been discussed, the corresponding brake values must be accounted for which will take into account other losses such as friction, pumping during the intake and exhaust strokes, and accessory loads such as the alternator or generator. In addition to these sources, unique to the plasmatron engine, is a loss in chemical energy that results from partially oxidizing the fuel that flows through the plasmatron. Since the efficiency quantities, which are arrived from the fuel-air cycle analysis, are based on the total chemical energy available that enters the cylinder, not the plasmatron, the chemical energy loss through the plasmatron has not been accounted for in the indicated fuel conversion efficiency, so we must account for this in the brake efficiency.
In addition to the benefit that we get to the indicated efficiency which relates to the compression and expansion strokes of the engine only, when the engine runs lean and more dilute, it will also be less throttled at low to mid power. Therefore, a benefit in terms of the pumping losses can also be estimated.
The pumping mean effective pressure (a normalized quantity for pumping work) can be approximated by the difference between the intake pressure and the exhaust pressure.
This approximation is somewhat limited because it ignores other sources of pressure loss and momentum during the engine breathing process. After having said this, again, we are looking to estimate the magnitude of the change in pumping loss due to the plasmatron, or lean condition. If we assume that the benefit is proportional to the change in the ratio of intake pressure minus exhaust pressure over the brake mean effective pressure (the normalized brake torque of the engine), we will have a good approximation of the benefit. For example, if the intake pressure at a given operating condition can be raised
by 35kPa due to the plasmatron, and brake mean effective pressure (BMEP) is 500 kPa, and without the plasmatron the indicated mean effective pressure (IMEP) is 650 kPa, the
IMEP with the plasmatron becomes 615 kPa and the % fuel conversion efficiency benefit can be calculated as
38

7b7f
%benefit = '''7"'""""
- 7 j
100 = y; i
500/615 - 500/650
5060
500 /650
-100 = 5.7% .
The next step is to determine the actual inlet pressures with and without the plasmatron.
One way to do this would be to create a flow model which can calculate the mass flow rate of air for given inlet pressures, and assuming some engine efficiency values, calculate the indicated engine torque for a given speed. A simpler approach is to look at an engine speed indicative of the most frequent operation, say 2000 RPM, and calculate the inlet pressure versus load relationship from that. To make our job easier, we might use a pre-existing engine simulation code for this. The task is to determine the inlet pressure for an engine versus load, and then generate the same data for an engine running lean.
4.3 Chemical efficiency of the plasmatron
Since the plasmatron itself relies on an exothermic reaction to produce hydrogen from the fuel, some of the fuel's available chemical energy is lost in this chemical reaction. As stated previously, the ideal chemical reaction of the plasmatron is
C
7
H
4
+3.5(0
2
+3.773N
2
)
=
> 7CO +7H
2
+13.21N
2 for some percentage of the fuel and air passing through the plasmatron. We can calculate the actual percent of chemical energy released through this reaction from [8] m1n2 - LH + mco LHVco
I nfuei -LHVei
39

where, for every gram of fuel that is reacted there is 0.144 grams of H2 and 1.997 grams of CO. The resulting release is 15% of the fuels energy. Since the plasmatron efficiency
[8] is defined as
77ls= mH
2
-LHVH2 + mCO - LHVco mfuel
*LHVf,,
1
IC the efficiency of the ideal plasmatron is 85%. These values will vary minimally for different fuels; however, for gasoline type fuels the variation is less than +/- 0.5 to 1.0 %.
Realistically, some of the fuel-air mixture that passes through the plasmatron will be completely oxidized. Since the real plasmatron gas will then have some CO
2 and H
2
0 as well, the mass flow rates of H
2 and CO will be reduced for a given mass flow rate of fuel.
As a result, the current projected efficiency of a real plasmatron is assumed to be about
80%.
4.4 Electrical energy requirements
Current development efforts of the plasmatron reformer indicate that the device may operate with as low as 200W of electrical power. Given the efficiency of generating that electrical power through the engine's accessory drive system and a generator or alternator, the actual engine brake power required to generate 200W of electrical power might be 400W; meaning that the electrical generating efficiency is about 50%. Since the hydrogen generation rate will vary with engine operation, the power requirement of the plasmatron will also vary. Current estimates are that the device will require 4MJ of electrical energy per kg of hydrogen generated, thus 8MJ of brake engine energy will be required for every kg of H
2
. An electrical energy model can be assumed that requires a minimum of 400W or 8MW at the engine crank per kg/s of H
2
.
40

Table 4.1 Electrical MEP (kPa) At the Engine Crankshaft
12%
RPM 800 15.8
1500 8.4
3000 4.2
45001 3.5
60001 3.5
24%
15.8
8.4
4.7
4.7
4.7
36%
15.8
8.4
5.9
5.9
5.9
48%
15.8
Load
8.4
7.1
7.1
7.1
60%
15.8
8.4
8.4
8A4
8.4
72%
15.8
9.7
9.7
9.7
9.7
84%
15.8
11.0
11.0
11.0
11.0
100%
15.8
12.6
12.6
12.6
12.6
Table 4.1 is an example of such a model for the electrical MEP (EMEP) requirement at the engine crank. Above the solid black line, the hydrogen requirement is low such that at 8MW per kg/s of H
2 there will be less than the minimum 400W of engine power required, so the EMEP required to produce 400W is calculated. We can see that this is dependant on the engine speed, but independent on the load. Below the solid line, the 8
MW per kg/s exceeds 400W, so the EMEP is based on the 8MW per kg/s requirement only. We can see that this EMEP is independent of engine speed, but dependant on load.
Based on the drivetrain design and operation, engines typically do not operate at high speeds and very low loads, and likewise, they do not frequently operate at very low speeds and very high load. The typical envelope of the engine's actual operation is shown in the highlighted part of the table above.
Based on this, it is possible to approximate the EMEP over 36% load as independent of engine speed. Below 36% load, the EMEP will typically vary between 8.4 and 15.8 kPa depending on the speed. Since significant operation occurs at both these speeds, one could assume an average 12.1 kPa of EMEP below 36% load, and the errors, for the most part, would cancel out. The model for EMEP could then be simplified to the values in
Table 4.2. It is important to note that the values will change with the engine size.
Table 4.2 Simplified Electrical MEP (kPa) Versus Load Only
12%
EMEP (kPa) 12.1
24%
12.1
36%
5.9
48%
Load
7.1
60%
8.4
72%
9.7
84%
11.0
100%
12.6
41

4.5 The effects of friction
It is not expected that the mechanical and accessory engine friction (other than the electrical power generation loads which have already been covered) would be directly impacted by running plasmatron gas through the engine. A simplifying assumption is that friction has a constant component, and a component that is dependent on engine speed effects. The effects of load on friction can be assumed secondary to speed. The next question to be addressed is whether the speed-varying component of friction will have an appreciable effect on the percent SFC reduction due to the plasmatron. In other words, do we need to book keep the percent SFC reduction versus speed due to the friction-speed dependency?
Hypothetically, we can model a case where friction is constant at a mfMEP of 100 kPa, calculate the SFC savings based on an indicated efficiency improvement typical of X=1.7 versus stochiometric, along with associated change in pumping losses and a constant
EMEP of 15 kPa. Next, we can model the same scenario while varying the mfMEP according to Table 4.3.
Table 4.3 Example of Friction MEP Versus Speed
RPM mfMEP (kPa)
800
1500
3000
60
80
100
4500
6000
120
140
By comparing the SFC reduction percentages, an estimate of the nominal error in the
SFC reduction percentage over the envelope of operation is shown in Table 4.4.
42

Table 4.4 Nominal Error (% SFC Reduction) Constant Friction of 100 kPa versus mfMEP in Table 4.3
RPM 800
1500
3000
4500
6000
12%
~
0.2%
IU
0.1%
0.0%
-0.1%
-0.1%
24%
0.0%
0.0%
0.0%
0.0%
0.0%
36%
36%
-0.1%
-0.1%
0.0%
0.1%
0.1%
Load
48%
-0.1%
-0.1%
0.0%
0.1%
0.1%
60%
U1o
-0.1%
0.0%
0.0%
0.0%
0.1%
72%
Uo
0.0%
0.0%
0.0%
0.0%
0.0%
84%
U.U7
0.0%
0.0%
0.0%
0.0%
0.0%
100%
U7
0.0%
0.0%
0.0%
0.0%
0.0%
The conclusion can easily be drawn that it is not necessary to book keep SFC reduction as a function of the speed dependence of mechanical and accessory friction MEP.
In conclusion, Figure 4.4 shows a simple approximation of the plasmatron benefits to brake fuel conversion efficiency. The left hand portion of the figure shows the fundamental gains due the plasmatron, and the right side shows the losses that partially offset these benefits.
0.29
0.327
0.34
Brake Fuel Conversion Efficiency
0.37
0.355
0.34
0.31
Baseline
Si engine
Eff
Lean engine cycle benefit
Reduced pumping loss
Increased
Compression ratio
Electrical
Energy
Requirement
Plasamatron
Gas
Efficiency
Best Efficiency to
Average efficiency over driving cycles
N.A. I turbocharged
Figure 4.4 Summary of Net Plasmatron Benefits
43

44

CHAPTER V: LIFE CYCLE COST MODEL
How does one predict the success of a developing technology? How does one assess how much benefit will be enough to justify further development? Should development, production, and distribution costs be compared to the total life cycle benefits of the technology? How much net benefit would justify using a new, more complicated, or higher risk technology? How much would a consumer be willing to pay for the benefits of this product?
I would like to be able to address and answer all of these question and more for the plasmatron technology with this research. These are difficult, multidimensional questions. As an analyst, and especially, as a student at MIT, my job should be to determine two numbers; A is the net of all costs and benefits from well to wheels to the scrap heap of vehicle A, and B is the net of all costs and benefits from well to wheels to the scrap heap of vehicle B. The conclusion is very simple, if A is higher than B, and A is a plasmatron vehicle, and B is the best available alternative vehicle to vehicle A, then the technology behind vehicle A ought to be developed, and invested in.
This being said, the numbers A and B must account for everything. Examples of
"everything" include the timing of the availability of the vehicles, the discounting of dollars or NPV (net present value), the value of the emissions benefits, the long term effects on changing the supply demand equation in international energy markets, and the risk adjustment and utility functions to deal with the relative risks associated with A versus B. As you can see, this simple decision model becomes very difficult to implement when all the details are considered. Also, it is clear that business decisions are made everyday without having this data and analysis available. This is not to say that the decisions are made without data, however, they are made without exact knowledge of A and B. Going further, it would be difficult to be competitive in today's market place if businesses were to take the time to complete such analysis for every important decision.
Rather than knowing A and B, I would suggest that data and analysis be presented to build a case that A might be, with some confidence, greater than B.
45

Another way of analyzing this problem this might be the following example; If there will be some additional cost to develop and produce vehicle A (the incremental cost is unknown) and the main source of savings will be fuel costs over time, and we calculate the fuel cost savings to be $100 over the vehicles lifespan over vehicle B, it may not be useful to develop vehicle A. Reasons for making this decision might be that any reasonable development effort might require more than $100 per vehicle to recover, most consumers would not readily consider a savings over a vehicles lifetime of $100 as a consideration for purchasing vehicle A over vehicle B, and maybe finally, the risks and uncertainties in the analysis are of comparable magnitude or greater magnitude than the total savings, and thus there is the real probability that the savings will be zero, or negative.
In summary, this thesis will attempt to provide some key metrics that can be used to evaluate the plasmatron, rather than exact estimates for A and B. Some useful metrics are as follows:
" The annual monetary savings due to fuel savings of the plasmatron vehicle versus a conventional vehicle without a plasmatron
" The level of complexity of the plasmatron engine versus a conventional baseline with no modifications
* The City and Highway MPG estimates of the plasmatron vehicle and that of a similar conventional vehicle
" The net present value of the fuel savings over the vehicles lifetime
" The sensitivity of these estimates to the type of vehicle usage and annual milage
The important drive cycles have been defined. ADVISOR has been used to simulate a vehicle and translate a vehicle mission into an engine mission. At each time step in the mission, the energy in kWhr is calculated based on the speed, torque, and length of each timestep. Also, using the speed and torque, the specific fuel consumption g/kWhr is interpolated off of the engine performance maps for the plasmatron engine and baseline engine. The specific fuel consumption times the energy used gives the mass of fuel used
46

in that timestep. The total mass of all the fuel used for each drive cycle, given the distance covered in miles, can be converted to a MPG number for each cycle.
Having the fuel economy, the total annual fuel cost can be calculated for each drive cycle when coupled with the model for fuel prices each year. With an annual cost stream, the net present value is a simple calculation.
47

48

CHAPTER VI: DISCUSSION OF RESULTS
6.1 Case 1. Naturally Aspirated Engine; Compression Ratio of 10.
The experiments conducted to date at the MIT test facility have taken place on a naturally-aspirated single-cylinder test engine with a compression ratio of about 10. The experiments [8] consisted of 10%, 20%, and 30% of the total fuel through the plasmatron simulated using bottled gases with ever increasing air-fuel ratios until unstable combustion was achieved. The test showed that stable operation was possible on this engine setup with k=1.7 (or perhaps higher) with plasmatron gas levels between 10% and
30%. For a starting point for this analysis, k=1.7 with 20% plasmatron gas is assumed.
The indicated fuel conversion efficiency is improved from 0.385 to 0.436 by increasing
k from 1.0 to 1.7, which gives an improvement of about 13% (note that the absolute efficiency differs from the fuel-air cycle to account for a "real engine" however; the % improvement is consistent with the fuel-air cycle results).
The brake fuel conversion efficiency accounts for the friction, pumping losses, electrical loads from the plasmatron, and the chemical energy losses in the plasmatron. The additional chemical energy losses and electrical loads are partially offset by a reduction in pumping losses as a result of the plasmatron. The peak improvement is about 11% in terms of brake fuel conversion efficiency.
49

0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
C
Brake Fuel Conersion Efficiency
12.0%
........
~ ...
~
10.0%
8.0%
6.0%
-
4.0%
2.0%
0.0%
13% 26% 39% 52%
Load
65% 78% 91%
-+- Eta [brake fuel conv baseline]
-- Eta [brake fuel conv lean]
SFC
Improvement %
Figure 6.1 Brake Fuel Conversion Efficiency Versus Load & % SFC Reduction
As can be seen in Figure 6.1, at about 60% load the benefits of the plasmatron are lost as the fuel-air ratio jumps back to stochiometric so that a three way catalyst can be used to cope with the increasing NOx emissions.
The plasmatron improvements have been run through the models for the Large Car and
Small Car as well as the three drive cycles and the results are shown in the figures that follow. Due to the loss in benefits of the plasmatron at higher loads, the net savings for the US06 cycle operation shows the largest deficit. This is because the US06 cycle contains the harshest accelerations out of the four cycles, and therefore utilizes the higher loads the most. See tables 6.1 through 6.4.
Table 6.1 Case 1.
Large Car Plasmatron MPG and Fuel Consumption Results
MPG Baseline
FTP
17
HWY
34
USO6
21
19 38 22 MPG Plasmatron
Total Fuel
Consumption
Reduction
7.9% 8.7% 5.4%
50

Table 6.2 Case 1. Large Car Fuel Savings Net Present Value Results
Fuel Savings NPV ($ 2002)
FTP (13K Miles/year)
HWY (13K Miles/year)
US06 (13K Miles/year)
Payback Period (years)
1 2 3 4 5 6 7 8
166 243 315 383 447 508 566 620
93 136 176 214 250 284 316 346
93 136 176 214 250 284 316 346
9
671
375
375
10
719
402
402
Table 6.3 Case 1. Small Car Plasmatron MPG and Fuel Consumption Results
MPG Baseline
FTP
27
HWY
44
US06
32
MPG Plasmatron 29 48 34
Total Fuel
Consumption
Reduction
8.3% 9.3% 6.6%
Table 6.4 Case 1. Small Car Fuel Savings Net Present Value Results
Fuel Savings NPV ($ 2002)
FTP (13K Miles/year)
HWY (13K Miles/year)
USO6 (13K Miles/year)
1
112
77
75
2
164
112
110
3
213
145
143
Payback Period (years)
4 5 6 7 8
259 302 343 382 419
177 207 235 261 286
173 202 230 256 280
9
453
310
304
10
486
332
326
Tables 6.2 and 6.4 show the net present value (NPV) of the fuel savings over a payback period of 1 to 10 years. For example, the results show that for the large car, and initial investment of an incremental $400-$720 vehicle cost could be offset with fuel savings over a 10 year payback time depending on which drive cycle is most representative.
Alternatively, depending on the drive cycle, one would save $90-$170 in fuel expenditures over the first year of operation. In addition, it can be said that each year, the nominal fuel savings will be $90-$170.
Since there will be an incremental cost for the plasmatron within the order of magnitude of hundreds of dollars, we can see that we have some potential for viability, however the results seem marginal. Realistically, one train of thought is that one may expect that their
51

payback period be somewhat less than 10 year in order to accept the risks of investment in a new technology, or even more simply, just not care to look out further than three to five years. Reviewing table 6.2, we can assert that for most driving conditions, the net present value of the fuel savings will be at least about $200 to $300 over a 3 to 5 year payback period. This result is not remarkable, however, it does show some promise that the fuel savings has the potential to justify some of the plasmatron cost to the consumer without considering any other benefits.
Alternatively, $200 to $300 in the US market may translate into $400 to $600 in another market where the fuel prices are double those of the US. In addition to this, there is a market of consumers (although a small market) who are willing to pay additional amounts for fuel savings even when the savings does not offset the initial costs, such as the consumers who currently purchase hybrid vehicles. The reasons for these purchasing decisions may be related to the social, and/or environmental benefits to reduced fuel consumption, which this study will not attempt to quantify.
The only other thing to note may be the differences between the small car and large car results. As mentioned earlier, the purpose of analyzing two vehicle types was to be able to have some idea as to the "economies of scale" factors involved, and perhaps, to quite simply have more than one data point since different engine/transmission combinations will differ in their relative times spent at given loads and speeds for a given drive cycle.
The results in tables 6.1 and 6.3 show that the relative reductions in fuel consumption, on a percentage basis, are very close for the two vehicles, except for the US06 cycle where the large car seems to be penalized more. The cause for this, perhaps, is that the large vehicle's engine is more heavily loaded during the hard accelerations in the US06 cycle causing it to operate more in the region where the plasmatron benefits are absent. On a dollar basis, the large vehicle has a significant advantage as shown in tables 6.2 and 6.4.
Since the large vehicle has such a higher fuel consumption to begin with, a common percentage in fuel consumption reduction translates in to many more dollars of savings for the large vehicle.
52

6.2 Case 2. Naturally Aspirated Engine; compression ratio of 14.
The results in section 6.1 showed that the plasmatron has promise, but to really justify the development of the device we must show the potential for further upside in terms of the fuel savings potential.
The next logical step is to increase the compression ratio from 10 to 14. The inherent problem that results from this, however, is at higher loads when the engine is switched to stochiometric operation. In this regime, the dilution benefits of running lean are lost, so the onset of knock may occur. To avoid this, some other solution will need to be devised
(e.g. some form of variable compression ratio). Setting this issue aside for the time being, the results that stem from an additional 9% improvement in the indicated fuel conversion efficiency and a 0% improvement above 60% load (assuming that the compression ratio returns to 10 while the engine is stochiometric) can be reviewed.
0.45
1~
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
C
Brake Fuel Conversion Efficiency
20.0%
18.0%
16.0%
14.0%
12.0%
10.0%
8.0%
6.0%
4.0%
2.0%
0.0%
13% 26% 39% 52%
Load
65% 78% 91%
---
Eta [brake fuel conv baseline]
_n- Eta [brake fuel conv lean]
SFC
Improwment %
Figure 6.2 Case 2. Brake Fuel Conversion Efficiency Versus Load & % SFC
Reduction with rc=14
53

As can be seen in Tables 6.5, 6.6, 6.7, and 6.8, the benefits are increased due to increasing the compression ratio, however, the reduction in the peak benefit shown in
Figure 6.2 is still somewhat reduced by the engine mission of the US06 cycle. The other two drive cycles allow an acceptable reduction in the peak performance benefit, however, as might be expected, the US06 cycle, with its higher acceleration rates puts higher loads on the engine for more time forcing it into the region where there is no plasmatron benefit.
The losses of benefit with US06 cycle poses a problem to the system robustness since half or more than half of the potential plasmatron benefits are lost when coupled with this driving cycle. One possible solution for this might be to run the engine at the lean limit
(X=1.7) as long as possible as load increases, and instead of "jumping" to stochometric to allow use of a three way catalyst, the fuel-air ratio could be increased as necessary to meet the load requirements. This would not provide equal benefit to running at the lean limit all the time, but would allow some benefits at the higher loads.
The issue of NOx emissions would then need to be dealt with. Two schools of thought are possible here: One is that a detailed emissions analysis could be done to determine the impact of the time spent in this slightly lean area where NOx emissions are high and a three way catalyst does not work. The second idea might be to research the latest catalyst
& storage technologies to find an aftertreatment to make this regime feasible.
Table 6.5 Case 2. Large Car Plasmatron MPG and Fuel Consumption Results
MPG Baseline
MPG Plasmatron
Total Fuel
Consumption
Reduction
FTP
17
20
14.3%
HWY
34
40
15.5%
USO6
21
23
9.2%
54

Table 6.6 Case 2. Large Car Fuel Savings Net Present Value Results
Fuel Savings NPV ($ 2002)
FTP (13K Miles/year)
HWY (13K Miles/year)
US06 (13K Miles/year)
Payback Period (years)
1 2 3 4 5 6 7 8 9 10
301 439 570 693 809 919 1023 1121 1214 1301
164 240 311 378 442 502 559 612 663 711
159 232 302 367 428 487 542 594 643 689
Table 6.7 Case 2. Small Car Plasmatron MPG and Fuel Consumption Results
MPG Baseline
FTP
27
HWY
44
USO6
32
MPG Plasmatron 32 52 36
Total Fuel
Consumption
Reduction
15.1% 15.9% 11.2%
Table 6.8 Case 2. Small Car Fuel Savings Net Present Value Results
Fuel Savings NPV ($ 2002)
FTP (13K Miles/year)
HWY (13K Miles/year)
USO6 (13K Miles/year)
1 2 3
Payback Period (years)
4 5 6 7 8 9 10
203 296 385 468 546 620 691 757 819 878
132 192 250 304 355 403 448 491 532 570
128 187 242 295 344 391 435 477 517 554
Looking at the large car NPV results (table 6.6), and setting aside the US06 cycle and thus the issue of "jumping" to stochiometric at high loads and losing benefit, we can see that the savings is quite substantial. $160 to $300 per year in nominal savings, or $380 to
$810 on a 3-5 year NPV basis should provide real value to the end customers. This results could lead one to the conclusion, without considering other factors, that a rational end customer might be willing to spend an incremental $500 or so to have a plasmatron vehicle.
6.3 Case 3. Turbocharged Engine; compression ratio of 14.
The best solution to the dilemma presented in cases 1 & 2, where 50% or more of the potential benefits of the plasmatron are lost due to time spent at high loads in the US06 drive cycle, is to boost the engine. Rather than increase the fuel-air mixture at higher
55

loads, the engine could remain lean (at k=1.7), however, just enough boost from a turbo could provide the extra power needed to still achieve the same maximum load as the conventional engine. This strategy should provide basically no substantial losses in benefits over the drive cycles at the expense of the cost of the additional turbo hardware.
A simple thermodynamic model of the turbine and compressor is incorporated into the model. The assumed indicated efficiency while running lean does not change, however, this efficiency is applied over all loads as there is no longer a "jump" to stochimetric.
The inlet pressure is calculated (assuming that the incoming air can be cooled to 360K via an intercooler) such that the maximum BMEP for the engine is unchanged.
To calculate the right amount of boost, and ultimately, the right brake efficiency, an iterative process is required. This process begins with guessing a boost amount, then calculating the turbine inlet pressure via a work balance (turbine work output = compressor work input). Once the pressures are known, the BMEP is calculated based on the intake and exhaust pressures. For these calculations, reasonable assumptions are made about the turbine and compressor efficiencies. The resulting turbo parameters are shown in table 6.9.
Table 6.9 Turbo Parameters
Turbo Parameters
Boost Pressure (Bar - absolute)
Manifold Air Temperature (K)
Intercooler Pressure Drop (kPa)
Compressor Efficiency
Turbine Efficiency
1.49
360
5
0.75
0.75
56

Brake Fuel Conversion Efficiency
0.2
0.15
0.45
0.4
0.3
0.35
0.25
I
--
3/'
0.1
0.05
0
-M
13% 26% 39% 52% 65% 78% 91%
Load
18.0%
16.0%
14.0%
12.0%
10.0%
8.0%
6.0%
4.0%
2.0%
0.0%
-+- Eta [brake fuel conv baseline]
-N- Eta [brake fuel conv lean]
SFC
Improvement %
Figure 6.3 Case 3. Brake Fuel Conversion Efficiency Versus Load & % SFC
Reduction with r,=14 and Turbo
Table 6.10 Case 3.
Large Car Plasmatron MPG and Fuel Consumption Results
MPG Baseline
FTP
17
HWY
34
US06
21
20 41 25 MPG Plasmatron
Total Fuel
Consumption
Reduction
15.2% 15.6% 15.6%
Table 6.11 Case 3. Large Car Fuel Savings Net Present Value Results
Fuel Savings NPV ($ 2002)
FTP (13K Miles/year)
HWY (13K Miles/year)
US06 (13K Miles/year)
Payback Period (years)
1 2 3 4 5 6 7 8 9
319 465 604 734 857 974 1084 1188 1286
166 241 313 381 445 505 562 616 667
272 396 514 625 730 829 923 1012 1095
Table 6.12 Case 3. Small Car Plasmatron MPG and Fuel Consumption Results
FTP HWY USO6
MPG Baseline 27 44 32
MPG Plasmatron 32 52
38
10
1379
715
1174
Total Fuel
Consumption
Reduction
15.2% 16.1% 15.9%
57

Table 6.13 Case 3. Small Car Fuel Savings Net Present Value Results
Fuel Savings NPV ($ 2002)
FTP (13K Miles/year)
HWY (13K Miles/year)
US06 (13K Miles/year)
Payback Period (years)
1 2 3 4 5 6 7 8 9 10
205 299 388 472 552 627 698 765 828 887
134 195 253 307 359 408 454 497 539 577
182 265 344 418 488 555 618 677 733 786
As the data shows, the addition of a turbo offers a real benefit for the US06 cycle, however for the other dive cycles there really is no additional benefit. This result is important because an operator who drives mostly on the highway, or has seldom hard accelerations will get almost no benefit from the additional cost of the turbo. The results do not lead to an easy answer as to whether the turbo should be added, due to the dependency on the driving cycle, although, the turbo does negate the need to vary the compression ratio at high loads as had been required when the compression ratio was increased to 14 for the lean operation only. Also, as will be described in the next section, additional benefits from the turbo are possible which will impact all of the driving cycles.
On another note, though cases 1-3, the large car and small car have both been considered.
The relative difference between the two has been quantified, and little information will be obtained by continuing to use both vehicles in the cases that follow. Since the intent is to target the mid to larger sized car due to its economic attractiveness, the large car will be used for the results to follow.
6.4 Case 4. Reduced engine size facilitated by plasmatron and more boost
In cases 1 through 3, the major constraint has been that the overall engine size and technology has not changed, and only changes to the air-fuel mixture, compression ratio, and plasmatron gas were considered. In case 3, a turbo charger was added, however, only sufficient boost was added to maintain the same BMEP, and same engine displacement as the baseline engine to produce an identical maximum load. Given that the expense of adding a turbo-charger is required for case 3, it follows that the maximum benefits of the turbo ought to be sought, namely, higher amounts of boost and reduced engine size.
58

Another possible benefit of the plasmatron, however, is that the hydrogen mixture might allow for higher boost amounts than would otherwise be considered in a conventional spark ignition engine. In diesel engines, very high levels of boost and high compression ratios are achievable. A highly boosted plasmatron engine has not been tested, however, boost levels of 2.0 atm (absolute intake pressure) as well as a further increase in boost to
2.5 atm in the next section, will be considered.
The main benefit of increasing the boost, is that a smaller engine displacement can be used to generate the same torque due to a higher BMEP. As a result of the higher BMEP, the relative loss due to mechanical friction (including pumping losses) will be reduced.
With an intake pressure of 2.0 atm, the engine size for the large car can be reduced from
3.0 L to 2.2 L, and the BMEP at 2000 RPM is increased from 1000 kPa to 1390 kPa.
SFC Reduction vs Boost & Displacement
35.0%
-
30.0%
-
.i
25.0% 4
E
0 20.0%
o 15.0%
10.0%
U
U) 5.0%
0.0%
C %
-
T U
20% 40%
Load
60% 80% 100%
-+-
-U-
CR=14, Lambda=1.7, turbo,
1.0 atm Comp. Exit
Pressure (No Boost), 3.0 L
CR=14, Lambda=1.7, turbo,
1.5 atm Comp. Exit
Pressure, 3.0 L
CR=14, Lanbda=1.7, turbo,
2 atm Comp. Exit Pressure,
2.2 L
Figure 6.4 Reduced Engine Size SFC Reduction vs Load (Large Car)
59

Table 6.14 Average MPG vs Boost & Engine Size
MPG Baseline 3.0L
Plasmatron (1.0 atm) 3.0L
Plasmatron (1.5 atm) 3.0L
Plasmatron (2.0 atm) 2.2L
(FTP)_
17
20
20
23
(HWY) (US06)
34 21
41 23
41
46
25
26
5 year NPV Fuel Savings
$1,600
$1,400
$1,200
E
A (US06)
E B (FTP)
-
$1,000
0.
Z
$800
$600
$400
$200
$0
Plasmatron (1.0 atm) 3.0L Plasmatron (1.5 atm) 3.0L Plasmatron (2.0 atm) 2.2L-
Figure 6.5 5-Year NPV vs Boost and Engine size
6.5 Case 5. Sensitivity analysis and further potential gains
Since the modeling framework has been developed, it is very easy to examine other
"what if?" scenarios relative to the plasmatron engine performance. As with case 4, the large car model could be used to analyze the sensitivity of the benefit to some of the major assumptions regarding the plasmatron.
60

The analysis thus far has been based on a lean limit of %=1.7 as demonstrated in the experiments at MIT [8]. If a more advanced combustion system were to be used, or perhaps, the system could be tuned for quicker combustion, the lean limit might be extended and a higher k could be considered. To assess the possible impacts on the system, a hypothetical k=2.0 can be modeled, which will increase the indicated efficiency
by a factor of 1.018. If -2.0 is used in combination with the turbo, either the boost pressure will need to be increased, or X will need to be reduced at high load in order to meet the same maximum torque as the conventional engine. In either case, a boost schedule, a fuel-air schedule, and a throttling schedule would be required to control the engine.
Since there are many possible combinations of system configurations and control strategies, a more detailed system optimization would be required to determine the best design. Determining the optimal design is not the main goal here; rather, the main goal is to predict the likely system performance and economics. One possible way to analyze this scenario, would be to model the maximum possible benefit from the increase in
k. This would mean that k=2.0 would remain in effect for all loads since it produces the highest possible indicated efficiency, and the needed amount of boost would be used to ensure that the required maximum torque can be met.
In the design of the Plasmatron itself, there are a few areas for potential improvement.
One thing would be to improve the chemical efficiency of the Plasmatron. Since an efficiency of 0.85 is the maximum achievable due to energy release inherent with the chemical reaction, an efficiency improvement to 0.83 or 0.84 is within the realm of possibility. The other main area for the plasmatron efficiency is the electrical energy that is consumed. Both the consumption and transmission of the electrical power can be optimized. The electrical power requirement could be reduced by 50% to assess its sensitivity.
As a final potential improvement to the plasmatron engine gains, additional boost and a further reduction in the size of the engine can be contemplated. With an intake pressure
61

of 2.5 atm, the engine displacement is reduced to 1.7 L and the BMEP at 2000 RPM is
1760 kPa. To keep the analysis simple, the max engine speed is assumed to be identical to the baseline engine (typically, as engine size is reduced, the maximum engine speed can be increased which achieves nearly the same mean piston speed).
The results shown below illustrate the potential increases in plasmatron engine performance gains compared to case 4 and the baseline just described.
Plasmatron Sensitivity to Improvements
-+- CR=14, Lambda=1.7, turbo (case 4)
44.0%
-0- CR=14, Lambda=2.0, turbo (case 5a)
39.0%
CR=14, Lambda=2.0,
(case 5b) turbo, 84% plasma eff.
0
34.0%
29.0% x CR=14, Lambda=2.0, turbo, 84% plasma eff, reduce electrical power by 50% (case 5c)
24.0%
19.0%
14.0%
0% 20%
-m- CR=14, Lambda=2.0, turbo, 84% plasma eff, reduce electrical power by 50%, 15%
Plasmatron Gas (case 5d)
40%
Load
60% 80% 100%
-
CR=14, Lambda=2.0, turbo, 84% plasma eff, reduce electrical power by 50%, 15%
Plasmatron Gas, increased boost to 2.5 atm, displacement reduced to 1.7L (case 5e)
Figure 6.6 Potential Improvements to SFR Reduction vs Load (Large Car)
62

5 year NPV Fuel Savings
$2,500
$2,000
$1,500
0~ z
$1,000 -
0 B (FTP)
E C (HWY)
0 A (US06)
$500 -
$0 -
CR=14,
Lambda=1.7, turbo (case 4)
CR=14,
Lambda=2.0, turbo (case
5a)
CR=14,
Lambda=2.0, turbo, 84% plasma eff.
(case 5b)
CR=14,
Lambda=2.0, turbo, 84% plasma eff, reduce electrical power by
50% (case
5c)
CR= 14,
Lambda=2.0, turbo, 84% plasma eff, reduce electrical power by
50%, 15%
Plasmatron
Gas (case
5d)
CR=14,
Lambda=2.0, turbo, 84% plasma eff, reduce electrical power by
50%, 15%
Plasmatron
Gas, increased boost to 2.5 atm, displacement reduced to
1.7L (case
5e)
Figure 6.7 5-Year NPV of Potential Plasmatron Improvements
6.6 Case 6. "Transition Engine"
Referring back to cases 1 and 2 (the naturally aspirated plasmatron engine), the engine is first "leaned out", and then the compression ratio is increased from 10 to 14. The increase in compression ratio proves to be very important part of maximizing the plasmatron benefits, however, the problem is still unresolved relative to how one would reduce the compression ratio back down at high power where the engine will need to run
63

stochiometric. One possible solution to this issue, would be to create a configuration that makes some trade offs. For example, rather than having the engine return to stochiometric at high power, the engine could remain slightly lean (see Figure 6.8),
X=1.2, but would have to have a slightly larger displacement to compensate. Also, since the engine would be slightly lean at high power, the compression ratio can still be slightly higher. Instead of increasing the compression ratio to 14, some good benefit can be achieved by increasing the compression ratio to 12 with a much lower possibility of knock. The increase in BMEP due to the improved efficiency at this operating point will partially offset the need to increase the engine size. The result is that the 3.0 L engine in the large car will need to be increased to a 3.3 L displacement.
vs Load
1.6
1.5
1.8
1.7
e
1.4
1.3
1.2
1.1
1
0%
-W
10% 20% 30% 40% 50%
Load
60% 70% 80% 90% 100%
Figure 6.8 X vs load for "transition engine"
64

0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
0% 13% 26%
Brake Fuel Conversion Efficiency
78% 91%
12.0%
10.0%
8.0%
6.0%
-I
2.0%
--
-m-
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
SFC
Improvement %
0.0%
39% 52% 65%
Load
Figure 6.9
Case 6. Brake Fuel Conversion Efficiency Versus Load & % SFC
Reduction with rc=12, 1.2<X<1.7, and 3.3L Displacement
The brake fuel conversion efficiency and SFC improvement chart in Figure 6.9 shows that the peak SFC reduction is reduced from 18% to just over 10% when compared to case #2, but unlike cases 1 and 2, there is benefit over the entire load range without the need for a turbo. The peak benefit also corresponds to the most commonly used loads.
The deficit in peak benefits to case 2 is caused by the lower compression ratio, and the larger proportion of engine friction due to the increase in engine size. Since the benefits are more widespread than case 1, it is expected that the average benefits over a driving cycle will be better than case 1, but perhaps not quite as good as case 2.
Table 6.15 Case 6.
Large Car Plasmatron MPG and Fuel Consumption Results
MPG Baseline
B (FTP) C (HWY) A (US06)
17 34 21
19 37 23 MPG Plasmatron
Total Fuel
Consumption
Reduction
7.1% 7.9% 7.9%
65

Table 6.16 Case 6. Large Car Fuel Savings Net Present Value Results
Fuel Savings NPV ($ 2002)
FTP (13K Miles/year)
HWY (13K Miles/year)
US06 (13K Miles/year)
1 2 3
Payback Period (years)
4 5 6 7 8 9 10
149 217 282 343 401 455 506 555 601 644
84 123 160 194 227 257 287 314 340 364
136 199 258 314 366 416 463 508 550 589
Tables 6.15 and 6.16 confirm that case 6 is between case 1 and case 3 in terms of average fuel economy and fuel savings NPV. The major benefit over case 3 is that the "transition engine" is a more realistic possibility, as it does not need the variable compression ratio.
66

CHAPTER VII: LIMITATIONS
The basic modeling technique used for this research was to create data lookup tables for various aspects of engine performance, and combine the data in different ways to estimate propulsion system performance for a variety of possible system input parameters. The basic result is a relative estimate (relative to a baseline) of the potential fuel savings due to incorporation of a plasmatron. This model is not well suited as a design optimization tool, or a predictor of absolute vehicle and propulsion system performance. The idea, most simply stated, is to compare two points on a lookup table, and say for example, there is an X % benefit from going from one point to the next, and apply that X% gain to the known performance of a baseline system. The first point in the data table, of course, is selected to represent the baseline system, although, may not match an actual system because it is idealized in some fashion. The only complication to the above is that several "idealized" data tables are used, linear interpolation is applied, and simple internal combustion engine principles are applied to arrive at the results, or estimates.
Some of the data tables and sources of data are:
* % max IMEP vs Intake Pressure: data derived from GMR engine simulation
0 Rel. Pressure / Rel. Temp / Rel. Density / Enthalpy: Air Table
0 Indicated Efficiency vs rc & X: [Heywood] fuel-air cycle results
* Engine speed & torque vs time: Advisor vehicle simulation
* Baseline Engine SFC vs torque & speed: 1.9L & 3.OL engine data provided in
ADVISOR
The basic analysis assumes that an engine is operating at 2000 RPM, which is actually very close to where most passenger vehicle engines spend most of their time. The benefits at 2000 RPM are simply transferred to all other engine RPMs as a function of the percent of maximum load at that speed. This approximation generates an error that grows as the actual engine speed moves away from 2000 RPM, however, most dependencies on engine speed are secondary to the dependency on load. In figures 3.5 -
67

3.8, it can be seen that virtually all engine operation for the drive cycles studied occurs at
2000RPM +/- 1000 RPM, thus the errors due to speed dependency in this +/- 1000 RPM are very small.
Although idealized engine cycle data is used, it is used only as a means to scale the performance of an actual engine, so the final estimates should relate to a real engine.
In addition to the fact that the model is an estimation tool, many of the inputs and cases analyzed are based on speculation, or "what if" hypothetical scenarios. The scenarios should be used as design targets or goals, rather than a statement of what has been actually achieved. One example, is that a demonstrated 2=1.7 has been achieved in preliminary engine tests at MIT with bottled gas, but we speculate on the potential system performance if X=2.0 is achieved. These parameters are selected based on reasonableness and engineering judgment, rather than proven tests in many cases.
Finally, in order to really determine the feasibility of the plasmatron, the actual incremental manufacturing cost would need to be known for the device. Since the plasmatron has not been in mass production, this cost is not known. The device, is however, relatively simple and compact. In addition, some systems hypothesized require the use of a turbo and intercooler. The turbo and intercooler costs could be compared to other systems that are in production that require turbos. Preliminary estimates of the mature manufacturing costs of the plasmatron device, peg the cost at a few hundred dollars. Other control and electrical components will need to be factored into the final cost as well.
68

CHAPTER VIII: CONCLUSIONS
The testing to date has shown that lean operation is possible with the use of the plasmatron. If lean operation is facilitated as low as k=1.7, with the compression ratio remaining unchanged, nominal fuel saving benefits will result to the order of 5-10%. The dollar value of this savings if considered on an NPV basis over 5-years is about $300 which may be comparable to the additional cost of the plasmatron device itself, although this savings is not especially encouraging. Fortunately, there are many opportunities for improvement, and further development.
Theoretically, a higher compression ratio should be possible if running lean which can provide additional benefits. The main issue with this is that, at high power, where a stochometric mixture is needed, the onset of knock will occur. The solution to this is the use of a turbo, however the turbo will cause additional engine complexity and cost.
Although the cost of the turbo system is higher, it will allow many more possible system configurations including the possibility of reducing the engine size. The possibilities that the turbo systems facilitates can increase the benefits of the plasmatron from 5-10% fuel savings to a 20-30% fuel savings range. On an NPV dollar basis, over 5 years, the savings can exceed $1,000, and in other energy markets, $2,000. The trade off for this higher savings, is a more complex and costly system, as well as more uncertainty around whether the system will work.
A good way of evaluating the results would be to score each configuration according to its feasibility and compare to the potential benefits. For each of the cases studied, the system can be ranked according to its resistance to engine knock, the complexity of the hardware required, the complexity of the control system, and the level of confidence that the system will work. Assigning rating from 0-6, with 6 being the best, and 0 being the worst, the cases are scored as shown in Table 8.1.
69

Table 8.1 Feasibility Score Table
Knock
Hardware control confidence total score
SFC Reduction baseline
(CR=10, NO case 1
PLASMATRON) (CR=10)
6
6
6
6
24
0.00%
6
6
22
5
5
7.19% case 2
(CR=14)
5
5
0
5
15
12.75% case 3
(CR=14, 0.5 atm Boost) case 4 (1 atm Boost, case 5a reduced (sensitivity to engine Lambda) size)
4
4
5
5
18
15.43%
3
2
5
4
14
23.87%
3
2
5
3
13
25.94% case 5b
(sensitivity to plasmatron efficiency)
5
2
3
2
12
26.55% case 5d case 5e case 5c (sensitivit (sensitivit case 6
(sensitivity to y to % further ("transition electrical power) Plasmatr increase engine") on Gas) d boost)
3
2
5
1
11
27.31%
3
2
5
2
1
5
0
10
0
8
27.97% 32.11%
5
5
5
5
20
7.54%
In table 8.1, the benefit as measured by a composite reduction in SFC over the three cycles is included in the bottom row. A plot of the total benefit (composite SFC reduction) versus the feasibility score is shown in figure 8.1. A somewhat linear relationship exists between how feasible the system is versus the potential benefits.
SFC Reduction vs Feasibility Score
35.00% -
30.00%
25.00%
.C
20.00%
15.00%
10.00% i
5.00% 1
0.00%
5 10 15 feasibility score
Figure 8.1 SFC Reduction vs Feasibility Score
20
70

REFERENCES
[1] "Annual Energy Outlook 2002 with Projections to 2020" Energy Information
Administration, www.eia.doe.gov
[2] "Effectiveness and Impact of Corporate Average Fuel Economy (CAFE)
Standards." National Academy Press, Washington, D.C. , 2002.
[3] Heywood, J. B. Internal Combustion Engine Fundamentals, McGraw Hill, Inc.,
New York, 1988.
[4] "Household Vehicles Energy Consumption 1994", prepared by Energy
Information Administration, DOE/EIA-0464(94)
[5] Kosto, Martin E. "Modeling and Comparison of Transient Emissions Behavior of
Hybrid and Conventional Vehicles." M.S. Thesis, Massachusetts Institute of
Technology, 2001.
[6] Personal Correspondence, Jennifer Topica, 2002
[7] Personal Correspondence, Rudy Smalling, 2002
[8] Tully, Edward J. "Lean-Bum Charactoristics of a Gasoline Engine Enriched with
Hydrogen from a Plasmatron Fuel Reformer." M.S. Thesis, Massachusetts
Institute of Technology, 2002.
[9] www.epa.gov
71

72

Appendix A List of Assumptions and Selected Results
Assumption Group a b d e baseline (CR=10,
NO
P[.ASMATRON) case 1
(CR=10) case 4 case 2 case 3
(CR=14) (CR=14, 0.5 atm Boost)
(CR=14, 1 atm
Boost, reduced engine size) case 5a
(sensitivity to
Lambda) new description
Engine
Engine Size (Disp.) (small car / Large Car)
Compression Ratio
Analysis RPM (then scaled to entire RPM range)
% Gas Through Plasmatron
Plasmatron Efficiency
Lambda min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q
[HV] max BMEP
FrMEP (kPa)
Boost (atm)
1.9L / 3.0L
10
2000
0
0.8
1
0.4
8
43.1
1000
80
0
1.9L
10
1.7
/
20
0.8
0.4
80
0
3.0L
2000
8
43.1
1000
1.9L / 3.0L
14
2000
20
0.8
1.7
0.4
8
43.1
1000
80
0
1.9L / 3.0L
14
2000
20
0.8
1.7
0.4
8
43.1
1000
80
0.5
Manifold
Temp (k)
Max Pressure (atm)
350
1
350
1
350
1
360
1.45
360
1.95
Turbo
Compressor Efficiency
Turbine Efficiency
Intercooler Pressure Drop (atm)
Intercooler Exit Temp (K)
Working Fluid Compressor
Working Fluid Turbine
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.75
0.75
0.05
360 air air
0.75
0.75
0.05
360 air air
Financial
CPI (annual change %)
Discount Rate (annual %)
Payback Period (years)
Selected Results (Large Car)
Peak SFC Reduction
Average SFC Reduction composite*
5 year NPV Fuel Savings Composite* 2002
MPG composite*
$'s
4
10
1-10
0.00%
0.00%
0
21
10
4
1-10
10.32%
7.19%
316
24
4
10
1-10
16.96%
12.75%
560
26
10
4
1-10
16.96%
15.43%
678
26
* The composite values are based on 1/3 of miles on FTP cycle, 1/3 on the HWFET cycle, and
*/3 on the US06 cycle
4
10
1-10
28.07%
23.87%
1048
29
N/A / 2.2L
14
2000
20
0.8
1.7
0.4
8
43.1
1390
80
1
N/A / 3.0L
14
2000
20
0.8
2
0.4
8
43.1
1000
80
0.5
360
1.45
0.75
0.75
0.05
360 air air
4
10
1-10
30.51%
25.94%
1139
30 g case 5b
(sensitiity to plasmatron efficiency) h j case 5c
(sensitivity to electrical power) case 5d
(sensitivity to
Plasmatron
Gas) case 5e
(sensitivity to further increased boost) k case 6
("transition engine")
N/A / 3.0L
14
2000
20
0.84
2
0.4
8
43.1
1000
80
0.5
360
1.45
0.75
0.75
0.05
360 air air
4
10
1-10
31.08%
26.55%
1166
30
N/A / 3.0L
14
2000
20
0.84
2
0.2
4
43.1
1000
80
0.5
360
1.45
0.75
0.75
0.05
360 air air
4
10
1-10
32.32%
27.31%
1199
31
N/A / 3.0L
14
2000
15
0.84
2
0.2
4
43.1
1000
80
0.5
N/A / 1.7L
14
2000
15
0.84
1.7-2.0
0.2
4
43.1
1777
80
1.5
360
1.45
0.75
0.75
0.05
360 air air
10
4
1-10
32.87%
27.97%
1228
31
360
2.45
0.75
0.75
0.05
360 air air
4
10
1-10
40.13%
32.11%
1410
33
N/A / 3.3L
12
2000
20
0.8
1.7
0.4
8
43.1
1000
80
0
350
1
N/A
N/A
N/A
N/A
N/A
N/A
4
10
1-10
11%
7.54%
331
24
73

74

Appendix B.1 Baseline Engine SFC
Small Car: 1.9L engine Baseline SFC (g/kWhr) Assumption Group a. speed (rad/s) 52
105
157
209
262
314
367
419
471
524
576
628
468
522
540
684
756
756
16
612
612
612
594
558
522
31
443
403
407
396
382
365
340
356
392
461
511
529
47
371
337
346
335
320
311
288
318
351
378
421
432
281
304
317
333
365
374
62
331
308
306
301
284
279
78
306
284
281
275
266
263
277
283
293
306
328
335 torque (N-m)
94
313
286
263
259
247
256
267
275
279
284
295
313
109
302
283
255
245
245
248
259
263
272
283
299
299
125
248
254
270
279
295
295
324
284
247
245
245
245
140
263
273
283
292
292
288
288
252
248
245
245
248
156
288
288
288
263
256
259
263
266
275
284
290
288
172
288
288
288
288
288
288
288
288
288
288
288
288
Large Car:3.OL engine Baseline SFC (g/kWhr) Assumption Group a. speed (radls) 129
191
249
311
339
367
434
472
511 torque (N-m)
27 41
436
54 68 81 95 108 122 136 149
422 408 394 394 394 394 394 394 394
401
363
385
395
387 372 358 344 330 316 301 301 301
363 353 348 343 332 327 322 311 306
385 385 368 351 338 334 329 324 322
395 395 371 347 325 319 314 311 314
406
407
592
732
406 406 374 342 312 305 298 298 306
407 407 395 382 372 370 368 370 375
592 554 517 461 442 423 413 403 410
732 572 539 506 477 473 468 469 470
163 176 190
394 394 394
301 301 301
301 288 288
320 320 320
317 328 340
315 337 360
380 391 403
423 436 488
477 484 484
203 217
394 394
301 301
288 288
401 401
412 412
423 423
420 438
488 488
484 484
75

Appendix B.2 Case 1. Plasmatron, N.A., r,=10 Engine SFC
Small Car: 1.9L Plasmatron engine SFC (g/kWhr) Assumption Group b.
speed (rad/s) 52
105
157
209
262
314
367
419
471
524
576
628
476
426
476
492
623
689
689
16
558
558
558
541
508
31
401
365
369
359
346
331
308
323
356
418
463
480
47
334
303
311
301
288
280
259
286
316
340
379
389
62
296
275
274
269
254
249
251
272
283
298
327
335
78
274
255
252
247
239
236
249
253
263
274
294
300 torque (N-m)
94
282
258
237
233
222
230
241
248
251
256
266
282
109
288
269
242
233
233
236
247
250
259
270
284
284
125
324
284
247
245
245
245
248
254
270
279
295
295
245
245
248
263
273
283
292
292
140
288
288
252
248
156
288
288
288
263
256
259
263
266
275
284
290
288
172
288
288
288
288
288
288
288
288
288
288
288
288
Large Car: 3.OL Plasmatron engine SFC (g/kWhr) Assumption Group b. speed (racds) 129
191
249
311
339
367
434
472
511
27
404
371
337
357
366
376
377
549
678
41
388
356
334
354
364
373
374
545
673
54
372
340
322
351
361
370
371
506
522
68
356
324
314
333
335
338
357
467
487
315
311
307
343
413
454
81
353
309
307
95
354
297
299
304
292
281
334
398
430
108
355
285
295
301
288
275
333
382
426 torque (
122
355
272
290
136
363
278
287
297 299
283 287
29 275
332
373
422
342
372
433
149
383
294
298
313
306
298
365
399
458
317
315
380
423
477
163
394
331
301
320
176
394
301
288
320
328
337
391
436
484
340
360
403
488
484
190
394
301
288
320
2D3
394
3)1
288
401
412
423
420
488
484
217
394
3)1
288
401
412
423
438
488
484
76

Appendix B.3 Case 2. Plasmatron, N.A., r,=14 Engine SFC
Small Car: 1.9L Plasmatron engine SFC (g/kWhr) Assumption Group c. speed (rad/s) 52
105
157
209
262
314
367
419
471
524
576
628
16
527
527
527
511
480
449
403
449
465
589
651
651
31
378
344
347
338
325
312
290
304
335
393
436
451
47
311
282
290
281
269
261
242
266
295
317
353
362
62
273
254
253
248
235
230
232
251
261
275
302
309
78
253
236
233
228
221
218
230
234
243
253
271
277 torque (N-m)
94
261
238
219
216
205
213
223
229
232
237
246
261
109
277
259
233
225
225
228
238
241
249
260
274
274
245
248
254
270
279
295
295
125
324
284
247
245
245
245
248
263
273
283
292
292
140
288
288
252
248
245 256
259
263
266
275
284
290
288
156
288
288
288
263
172
288
288
288
288
288
288
288
288
288
288
288
288
Large Car: 3.OL Plasmatron engine SFC (g/kWhr) Assumption Group c. speed (rads) 129
191
249
311
339
367
434
472
511
27
374
344
312
330
339
348
349
DB
62B
41
359
3
309
3
337
345
347
5D4
623
54 68 81 95 108 taque("
122 136 149 163
345
315
32 327 2 32B 32 342
330 26 275
33
252 22
298 291
2M5
277 273 29 271
325
334
30B
310
2
28B
376 394
3 1
Z2 31
21 278 275 21 3)7 3)
271 257 22 271 300 317
343
344
469
484
313
330
433
451
234
318
383
42)
26)
310
368
39B
255
339
353
394
249
307
345
391
26)
3
351
408
293
358
32
449
315
380
423
477
176
394
301
MB
33)
32
337
391
436
484
340
33)
403
48B
484
190
394
203
394
217
34
3)1 301 301
28 288 M8
32) 401 401
412
423
42)
488
484
412
423
438
488
484
77

Appendix B.4 Case 3. Plasmatron, Turbo (0.5 atm Boost), r,=14 Engine
Small Car: 1.9L Plasmatron engine SFC (g/kWhr) Assumption Group d. speed (rad/s) 52
105
157
209
262
314
367
419
471
524
576
628
449
403
449
465
589
651
651
16
527
527
527
511
480
312
290
304
335
393
436
451
31
378
344
347
338
325
242
266
295
317
353
362
47
311
282
290
281
269
261
62
273
254
253
248
235
230
232
251
261
275
302
309
78
253
236
233
228
221
218
230
234
243
253
271
277 torque (N-m)
94
261
238
219
216
205
213
223
229
232
237
246
261
109
254
237
213
205
205
208
217
220
228
238
251
251
207
210
215
228
236
250
250
125
274
240
208
207
207
140
245
245
214
211
208
208
211
223
232
240
248
248
156
246
246
246
224
218
221
224
227
235
243
247
246
246
246
246
246
246
246
246
172
246
246
246
246
246
Large Car: 3.OL Plasmatron engine SFC (g/kWhr) Assumption Group d.
speed (rads) 129
191
249
311
339
367
434
472
511
.
27
374
344
312
330
339
348
349
508
62B
41
359
329
309
328
337
345
347
504
623
54
345
315
298
325
334
343
344
469
484
68
329
300
291
308
310
313
330
433
451
81
327
296
285
292
288
284
318
383
42D
95
328
275
277
281
271
260
310
368
398
108
328 329 330 331 333 334 335 336 337
33
252 253 254 255 256 256 2S7 258
273
278
267
269
275
262
31
258 254 245 245 246 247
271
261
271 270 271 272 342 343
34 268 279 29 352 353
255
122
249
136
250
149
258
163
266
176
296
190
306
203
361
217
362
309 tatue(Nn)
307 310 316 321 332 343 358 374
353
394
345
391
338
393
345
396
358
403
370
410
415
411
417
412
418
413
78

Appendix C.1 Plasmatron Model Assumption Group b case ! (CR =10)
Small Car
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (mA3)
20
0.8
1.7
0.5882
10
0.4
8
43.1
1000
0
80
0.002
baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean]
38.243
101.1
62.857
0.3853
45.957
101.1
55.143
50.62381
101.1
50.47619
61.480952 70.338095 78.124762
101.1 101.1 101.1
39.619048 30.761905 22.975238
85.593333
101.1
15.506667
95.348571
101.1
5.7514286
47.1
101.1
54
0.436
59.6
101.1
41.5
71.1
101.1
30
84.1
101.1
17
92.805
101.1
8.295
78.124762
101.1
22.975238
85.593333
101.1
15.506667
95.348571
101.1
5.7514286
Outputs
% max load
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
11%
114.8
257.66
260.3
0.1717
0.1846
23%
229.6
364.74
362.6
0.2425
0.265
34%
344.4
474.87619
459.68834
0.2794066
0.3135865
46%
459.2
578.81905
562.69242
0.305642
0.3415769
57%
574
684.7619
670.05031
0.3229433
0.3585603
69%
688.8
80%
803.6
791.77524
899.10667
791.77524 899.10667
0.3351546 0.3443362
0.3351546 0.3443362
100%
1000
1085.7514
1085.7514
0.3548326
0.3548326
11.5 11.5 5.2883372 6.4924213 7.7553074 9.1159573 10.344268 12.499296
0.2018 0.2867 0.337 0.366 0.383 0.391 0.402 0.414
486.6
452.48
7.0%
344.42
315.15
8.5%
298.94312
266.36
10.9%
273.28277
244.53
10.5%
258.64198
232.95
9.9%
249.21839
249.22
0.0%
242.57308
242.57
0.0%
235.39743
235.40
0.0%
83

Large Car
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (m^3) baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta jind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
20
0.8
1.7
0.5882
10
0.4
8
43.1
1000
0
80
0.003
38.243
101.1
62.857
0.3853
45.957
101.1
55.143
50.62381
101.1
50.47619
61.480952
101.1
39.619048
70.338095
101.1
30.761905
78.124762
101.1
22.975238
85.593333
101.1
15.506667
95.348571
101.1
5.7514286
44
101.1
57.1
0.4361
56
101.1
45.1
68
101.1
33.1
80
101.1
21.1
91
101.1
10.1
45.975 59.289 71.91238 83.88358 94.96932
78.124762
101.1
23.0
85.593333 95.348571
101.1 101.1
15.5 5.8
11%
114.8
257.66
259.57
0.1717
0.1852
23%
229.6
364.74
362.37
0.2425
0.2653
34%
344.4
474.87619
462.78834
0.2794066
0.3115485
46%
459.2
578.81905
566.79242
0.305642
0.3391741
57%
574
684.7619
671.85531
0.3229433
0.3576688
69%
688.8
791.77524
791.77524
0.3351546
0.3351546
80%
803.6
899.10667
899.10667
0.3443362
0.3443362
100%
1000
1085.7514
1085.7514
0.3548326
0.3548326
7.6667 7.6667 5.2883372 6.4924213 7.7553074 9.1159573 10.344268 12.499296
0.2018 0.2867 0.337 0.366 0.383 0.391 0.402 0.414
486.6 344.42 298.94312 273.28277 258.64198 249.21839 242.57308 235.39743
451.12 314.89 268.10 246.26 233.53 249.22 242.57 235.40
7.3% 8.6% 10.3% 9.9% 9.7% 0.0% 0.0% 0.0%
84

Appendix C.2 Plasmatron Model Assumption Group c case 2 (CR=14)
Small Car
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (mA3)
20
0.8
1.7
0.5882
14
0.4
43.1
8
1000
0
80
0.002
baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean]
38.243
101.1
62.857
0.3853
45.957
101.1
55.143
50.62381
101.1
50.47619
61.480952
101.1
39.619048
70.338095 78.124762
101.1 101.1
30.761905 22.975238
85.593333
101.1
15.506667
95.348571
101.1
5.7514286
47.1
101.1
54
0.471
59.6
101.1
41.5
71.1
101.1
30
84.1
101.1
17
92.805
101.1
8.295
78.124762
101.1
22.975238
85.593333
101.1
15.506667
95.348571
101.1
5.7514286
Outputs
% max load
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta (brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
11%
114.8
257.66
260.3
0.1717
0.1994
23%
229.6
364.74
362.6
0.2425
0.2863
34%
344.4
474.87619
459.68834
0.2794066
0.3387597
46%
459.2
578.81905
562.69242
0.305642
0.3689971
57%
574
684.7619
670.05031
0.3229433
0.3873438
69%
688.8
791.77524
80%
803.6
899.10667
791.77524 899.10667
0.3351546 0.3443362
0.3351546 0.3443362
100%
1000
1085.7514
1085.7514
0.3548326
0.3548326
11.5 11.5 5.2883372 6.4924213 7.7553074 9.1159573 10.344268 12.499296
0.2018 0.2867 0.337 0.366 0.383 0.391 0.402 0.414
486.6
418.86
13.9%
344.42
291.74
15.3%
298.94312
246.57
17.5%
273.28277
226.36
17.2%
258.64198
215.64
16.6%
249.21839
249.22
0.0%
242.57308
242.57
0.0%
235.39743
235.40
0.0%
85

Large Car
Inputs
% Gas Through Pasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (m^3) baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel ccnv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
20
0.8
1.7
0.5882
14
0.4
8
43.1
1000
0
80
0.003
38.243
101.1
62.857
0.3853
45.957
101.1
55.143
50.62381
101.1
50.47619
61.480952
101.1
39.619048
70.338095
101.1
30.761905
78.124762
101.1
22.975238
85.593333 95.348571
101.1 101.1
15.506667 5.7514286
44
101.1
57.1
0.471
56
/01.1
45.1
68
101.1
33.1
80
101.1
21.1
91
101.1
10.1
78.124762
101.1
23.0
85.593333
101.1
15.5
95.348571
101.1
5.8
43.466 55.814 67.69749 79.17219 89.83857
11%
114.8
257.66
259.57
0.1717
0.2
23%
229.6
364.74
362.37
0.2425
0.2865
34%
344.4
474.87619
462.78834
0.2794066
0.3364906
46%
459.2
578.81905
566.79242
0.305642
0.3663279
57%
574
684.7619
671.85531
0.3229433
0.3863032
69%
688.8
791.77524
791.77524
0.3351546
0.3351546
80%
803.6
899.10667
899.10667
0.3443362
0.3443362
100%
1000
1085.7514
1085.7514
0.3548326
0.3548326
7.6667 7.6667 5.2883372 6.4924213 7.7553074 9.1159573 10.344268 12.499296
0.2018 0.2867 0.337 0.366 0.383 0.391 0.402 0.414
486.6
417.68
14.2%
344.42
291.55
15.4%
298.94312
248.23
17.0%
273.28277
228.01
16.6%
258.64198
216.22
16.4%
249.21839
249.22
0.0%
242.57308 235.39743
242.57 235.40
0.0% 0.0%
86

Appendix C.3 Plasmatron Model Assumption Group d case 3 (CR=14, turbo)
Small Car
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (mA3)
20
0.8
1.7
0.5882
14
0.4
8
43.1
1000
1
80
0.002
baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean]
38.243
101.1
62.857
0.3853
45.957
101.1
55.143
50.62381
101.1
50.47619
61.480952
101.1
39.619048
70.338095
101.1
30.761905
78.124762
101.1
22.975238
85.593333
101.1
15.506667
95.348571
101.1
5.7514286
47.1
101.1
54
0.471
59.6
101.1
41.5
71.1
101.1
30
84.1
101.1
17
92.805
101.1
8.295
112
118.19711
6.1971127
125
127.25871
2.2587129
145.8
143.02076
-2.779238
Outputs
% max load
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
11%
114.8
257.66
260.3
0.1717
0.1994
23%
229.6
364.74
362.6
0.2425
0.2363
34%
344.4
474.87619
459.68834
0.2794066
0.3387597
46%
459.2
578.81905
562.69242
0.305642
0.3689971
57%
574
684.7619
670.05031
0.3229433
0.3873438
69%
688.8
80%
803.6
791.77524
899.10667
784.11307 896.20298
0.3351546 0.3443362
0.3971976 0.4054392
100%
1000
1085.7514
1089.7201
0.3548326
0.4149323
11.5 11.5 5.2883372 6.4924213 7.7553074 9.1159573 10.344268 12.499296
0.2018 0.2867 0.337 0.366 0.383 0.391 0.402 0.414
486.6
418.86
13.9%
344.42
291.74
15.3%
298.94312
246.57
17.5%
273.28277
226.36
17.2%
258.64198
215.64
16.6%
249.21839
210.29
15.6%
242.57308
206.02
15.1%
235.39743
201.30
14.5%
87

Large Car
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HVJ (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (m^3) baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PtXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta
[brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
20
0.8
1.7
0.5882
14
0.4
8
43.1
1000
1
80
0.003
38.243
101.1
62.857
0.3853
45.957 50.62381 61.480952 70.338095 78.124762 85.593333 95.348571
101.1 101.1 101.1 101.1 101.1 101.1 101.1
55.143 50.47619 39.619048 30.761905 22.975238 15.506667 5.7514286
44
101.1
57.1
0.471
56
101.1
45.1
68
101.1
33.1
80
101.1
21.1
91
101.1
10.1
112
118.2
6.2
125
127.3
2.3
145.8
143.0
-2.8
43.352 55.656 67.5028 78.95408 89.59986
11%
114.8
257.66
259.57
0.1717
0.2
23%
229.6
364.74
362.37
0.2425
0.2865
34%
344.4
474.87619
462.78834
0.2794066
0.3364906
46%
459.2
578.81905
566.79242
0.305642
0.3663279
57%
574
684.7619
671.85531
0.3229433
0.3863032
69%
688.8
791.77524
784.11307
0.3351546
0.3971976
80%
803.6
899.10667
896.20298
0.3443362
0.4054392
100%
1000
1085.7514
1089.7201
0.3548326
0.4149323
7.6667 7.6667 5.2883372 6.4924213 7.7553074 9.1159573 10.344268 12.499296
0.2018 0.2867 0.337 0.366 0.383 0.391 0.402 0.414
486.6
417.68
14.2%
344.42
291.55
15.4%
298.94312
248.23
17.0%
273.28277
228.01
16.6%
258.64198
216.22
16.4%
249.21839 242.57308 235.39743
210.29 206.02 201.30
15.6% 15.1% 14.5%
88

Appendix C.4 Plasmatron Model Assumption Group e case 4 (1 atm Boost, reduced engine size)
Ensyfte Disp. (r-^3)
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q
[HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (m^3)
Boost (absolute atm)
20
0.8
1.7
0.5882
14
0.4
8
43.1
1364.3
1
80
0.0022
2 baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP base (kPa)
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
38.2
101.1
62.9
0.385
49
101.1
52.1
0.471
48.6
11%
115
160
258
302
0.172
0.239
46.0
101.1
55.1
66
101.1
35.1
65.6
23%
230
319
365
445
0.243
0.324
50.6
101.1
50.5
81
101.1
20.1
81.2
34%
344
479
475
586
0.279
0.369
61.5
101.1
39.6
96
101.1
5.1
95.6
46%
459
638
579
732
0.306
0.394
70.3
101.1
30.8
125
127.5
2.5
57%
574
798
685
891
0.323
0.405
78.1 85.6
101.1
23.0
101.1
15.5
0.386 0.38665
137
138.6
1.6
69%
689
957
792
1052
0.335
0.412
158
154.8
-3.2
80%
804
1117
899
1208
0.344
0.418
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
10.7 10.7 7.4
0.202 0.287 0.337
486.6 344.4
350.0 257.5
28.1% 25.2%
298.9
226.2
24.3%
9.0
0 366
273.3
212.0
22.4%
10.8
0.383
258.6
206.3
20.2%
12.7
0.391
249.2
202.9
18.6%
14.4
0.402
242.6
199.8
17.6%
95.3
101.1
5.8
0.387
195
187.3
-7.7
100%
1000
1390
1086
1480
0.355
0.425
17.4
0.414
235.4
196.7
16.5%
89

Appendix C.5 Plasmatron Model Assumption Groupf case 5a (sensitivity to Lambda)
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
CIR (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp.
(mA3)
Boost (absolute atm) baseline
P!NT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta (ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP base (kPa)
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
20
0.8
2 2
0.5000 0.5000
14
0.4
8
43.1
1364.3
1
80
0.0022
2
38.2
101.1
62.9
0.385
46.0
101.1
55.1
54 73
101.1 101.1
47.1 28.1
0.479 0.479
53.6 72.6
11%
115
160
258
297
0.172
0.247
23%
230
319
365
438
0.243
0.335
10.7 10.7
0.202 0.287
486.6 344.4
338.1 249.0
30.5% 27.7%
2
0.5000
50.6
101.1
50.5
90
101.1
11.1
0.479
89.4
34%
344
479
475
577
0.279
0.382
7.4
0.337
298.9
218.8
26.8%
1.7
0.5882
61.5
101.1
39.6
96
101.1
5.1
0.471
95.6
46%
459
638
579
732
0.306
0.401
9.0
0.366
273.3
208.2
23.8%
1.7
0.5882
70.3
101.1
30.8
125
127.5
2.5
0.471
57%
574
798
685
891
0.323
0.412
10.8
0.383
258.6
202.7
21.6%
1.7
0.5882
78.1
101.1
23.0
137
138.6
1.6
0.471
69%
689
957
792
1052
0.335
0.419
12.7
0.391
249.2
199.4
20.0%
1.7
0.5882
85.6
101.1
15.5
158
154.8
-3.2
0.471
80%
804
1117
899
1208
0.344
0.426
14.4
0 402
242.6
196.3
19.1%
1.7
0.5882
95.3
101.1
5.8
195
187.3
-7.7
0.471
100%
1000
1390
1086
1480
0.355
0.432
17.4
0.414
235.4
193.2
17.9%
90

Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q
[HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp. (mA3)
Boost (absolute atm) baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP base (kPa)
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
Appendix C.6 Plasmatron Model Assumption Group g case5b (sensitivity to plasmatron efficiency)
20
0.84
2 2
0.5000 0.5000
14
0.4
8
43.1
1364.3
1
80
0.0022
2
38.2
101.1
62.9
0.385
46.0
101.1
55.1
54
101.1
47.1
73
101.1
28.1
0.479 0.479
53.6 72.6
11%
115
160
258
297
0.172
0.249
23%
230
319
365
438
0.243
0.338
10.7 10.7
0.202 0.287
486.6 344.4
335.4 247.0
31.1% 28.3%
2
0.5000
50.6
101.1
50.5
90
101.1
11.1
0.479
89.4
34%
344
479
475
577
0.279
0.385
7.4
0.337
298.9
217.0
27.4%
1.7
0.5882
61.5
101.1
39.6
96
101.1
5.1
0.471
95.6
46%
459
638
579
732
0.306
0.404
9.0
0.366
273.3
206.5
24.4%
1.7
0.5882
70.3
101.1
30.8
125
127.5
2.5
0.471
57%
574
798
685
891
0.323
0.416
10.8
0.383
258.6
201.0
22.3%
1.7
0.5882
78.1
101.1
23.0
137
138.6
1.6
0.471
69%
689
957
792
1052
0.335
0.422
12.7
0.391
249.2
197.7
20.7%
1.7
0.5882
85.6
101.1
15.5
158
154.8
-3.2
0.471
80%
804
1117
899
1208
0.344
0.429
14.4
0.402
242.6
194.7
19.7%
1.7
0.5882
95.3
101.1
5.8
195
187.3
-7.7
0.471
100%
1000
1390
1086
1480
0.355
0.436
17.4
0.414
235.4
191.6
18.6%
91

Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp.
(mA3)
Boost (absolute atm) baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] iean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP base (kPa)
BMEP (kPa)
IMEP base (kPa) iMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
Appendix C.7 Plasmatron Model Assumption Group h
Case5c (sensitivity to electrical power)
20
0.84
2 2
0.5000 0.5000
14
0.2
4
43.1
1364.3
1
80
0.0022
2
38.2
101.1
62.9
0.385
46.0
101.1
55.1
54
101.1
47.1
73
101.1
28.1
0.479 0.479
52.8 71.9
11%
115
160
258
292
0.172
0.254
23%
230
319
365
433
0.243
0.342
5.3 5.3
0.202 0.287
486.6 344.4
329.3 243.9
32.3% 29.2%
2
0.5000
50.6
101.1
50.5
90
101.1
11.1
0.479
89.0
34%
344
479
475
573
0.279
0.387
3.7
0.337
298.9
215.6
27.9%
1.7
0.5882
61.5
101.1
39.6
96
101.1
5.1
0.471
95.2
46%
459
638
579
728
0.306
0.407
4.5
0.366
273.3
205.2
24.9%
1.7
0.5882
70.3
101.1
30.8
125
127.5
2.5
0.471
57%
574
798
685
886
0.323
0.418
5.4
0.383
258.6
199.8
22.7%
1.7
0.5882
78.1
101.1
23.0
137
138.6
1.6
0.471
69%
689
957
792
1045
0.335
0.425
6.3
0.391
249.2
196.5
21.1%
1.7
0.5882
85.6
101.1
15.5
158
154.8
-3.2
0.471
80%
804
1117
899
1201
0.344
0.432
7.2
0.402
242.6
193.5
20.2%
1.7
0.5882
95.3
101.1
5.8
195
187.3
-7.7
0.471
100%
1000
1390
1086
1471
0.355
0.439
8.7
0.414
235.4
190.5
19.1%
92

Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q
[HV] (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp.
(mA3)
Boost (absolute atm) baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean]
Appendix C.8 Plasmatron Model Assumption Group I case 5d (sensitivity to % Plasmatron Gas)
15
0.84
2
0.5000
14
0.2
4
43.1
1364.3
1
80
0.0022
2
2
0.5000
38.2
101.1
62.9
0.385
46.0
101.1
55.1
54 73
101.1
47.1
101.1
28.1
0.479 0.479
2
0.5000
50.6
101.1
50.5
90
101.1
11.1
0.479
1.7
0.5882
61.5
101.1
39.6
96
101.1
5.1
0.471
1.7
0.5882
70.3
101.1
30.8
125
127.5
2.5
0.471
1.7
0.5882
78.1
101.1
23 0
137
138.6
1.6
0.471 pint (estimator) (kPa)
Outputs
% max load
BMEP base (kPa)
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpKWhr)
SFC nlasma (gpkWhr)
SFC Improvement %
52.8
11%
115
160
258
292
0.172
0.256
71.9
23%
230
319
365
433
0.243
0.345
5.3 5.3
0.202 0.287
486.6 344.4
326.6 241.9
32.9% 29.8%
88.9
34%
344
479
475
573
0.279
0.391
2.8
0.337
298.9
213.5
28.6%
95.1
46%
459
638
579
727
0.306
0.411
3.4
0.366
273.3
203.3
25.6%
57%
574
798
685
884
0.323
0.422
4.0
0.383
258.6
197.9
23.5%
69%
689
957
792
1044
0.335
0.429
4.8
0.391
249.2
194.6
21.9%
1.7
0.5882
85.6
101.1
15.5
158
154.8
-3.2
0.471
80%
804
1117
899
1199
0.344
0.436
5.4
0.402
242.6
191.6
21.0%
1.7
0.5882
95.3
101.1
5.8
195
187.3
-7.7
0.471
100%
1000
1390
1086
1469
0.355
0.443
6.5
0.414
235.A
188.6
19.9%
93

Appendix C.9 Plasmatron Model Assumption Groupj case 5e (sensitivity tojurther increased boost)
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q [HVJ (MJ/Kg) max BMEP (kPa) turbo (0/1)
FrMEP (kPa)
Engine Disp.
(mA
3)
Boost (absolute atm)
15
0.84
2 2
0.5000 0.5000
14
0.2
4
43.1
1714.16
1
80
0.00169
2.5
1.9
0.5263
1.7
0.5882
1.7
0.5882
1.7
0.5882 baseline
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv baseline] lean
PINT (kPa)
PEXH (kPa)
PMEP (kPa)
Eta [ind fuel conv lean] pint (estimator) (kPa)
Outputs
% max load
BMEP base (kPa)
BMEP (kPa)
IMEP base (kPa)
IMEP lean (kPa)
Eta [brake fuel conv baseline]
Eta [brake fuei conv lean]
EMEP (kPa)
Eta brake est
SFC baseline (gpkWhr)
SFC plasma (gpkWhr)
SFC Improvement %
38.2
101.1
62.9
0.385
46.0
101.1
55.1
59 82
101.1 101.1
42.1 19.1
0.479 0.479
58.5 82.0
11%
115
204
258
333
0 172
0.287
23%
230
408
365
514
0.243
0.371
6.8 6.8
0.202 0.287
486.6 344.4
291.3 224.8
40.1% 34.7%
50.6
101.1
50.5
99
101.1
2.1
0.478
98.7
34%
344
612
475
698
0.279
0.410
3.5
0.337
298.9
203.5
31.9%
61.5
101.1
39.6
117
119.9
2.9
0.471
46%
459
816
579
903
0.306
0.423
4.3
0.366
273.3
197.6
27.7%
70.3
101.1
30.8
144
143.2
-0.8
0.471
57%
574
1020
685
1104
0.323
0.432
5.2
0.383
258.6
193.3
25.3%
78.1
101.1
23.0
171
168.6
-2.4
0.471
69%
689
1224
792
1308
0.335
0.438
6.1
0.391
249.2
190.7
23.5%
1.7
0.5882
1.7
0.5882
85.6
101.1
15.5
198
192.0
-6.0
0.471
80%
804
1428
899
1509
0.344
0.443
6.9
0.402
242.6
188.6
22.2%
95.3
101.1
5.8
245
239.4
-5.6
0.471
100%
1000
1777
1086
1860
0.355
0.447
8.3
0.414
235.4
186.8
20.6%
94

Appendix C.10 Plasmatron Model Assumption Group k case 6 ("transition engine')
Inputs
% Gas Through Plasmatron
Plasmatron Efficiancy
Lambda
Phi
C/R (10 or 14) min elect power (kW) at crank
Elec Energy MJ/Kg H at crank
Q
[HV] max BMEP turbo (0/1)
FrMEP
Engine Disp. (mA3)
Boost
20
0.8
1.7
0.5882
12
0.4
8
43.1
0
0
80
0.0033
0
1.7
0.5882
12
1.7
0.5882
12
1.7
0.5882
12
1.7
0.5882
12
1.45
0.6897
12 baseline
PINT
PEXH
PMEP*
Eta [ind fuel conv baseline]* lean
PINT
PEXH
PMEP*
Eta [ind fuel conv lean]*
* from simulation pint (est)
Outputs
% max load
BMEP base
BMEP
IMEP base
IMEP lean
Eta [brake fuel conv baseline]
Eta [brake fuel conv lean]
EMEP 8MJ/Kg
Eta brake est
SFC baseline
SFC plasma
SFC Improvement %
38.2
101.1
62.9
0.385
34 41
101.1 101.1
51
101.1
67.1 60.1 50.1
0.464 0.464 0.464
34.4
46.0
101.1
55.1
43.1
11%
115
105
258
259
0.172
0.181
23%
230
210
365
357
0.243
0.262
7.0 7.0
0.202 0.287
485.6 344.4
462.7 318.8
4.9% 7.4%
50.6
101.1
50.5
51.3
34%
344
314
475
449
0.279
0.312
4.8
0.337
298.9
267.7
10.5%
61.5
101.1
39.6
60
101.1
41.1
0.464
59.8
46%
459
419
579
546
0.306
0.342
5.9
0.366
273.3
244.1
10.7%
70.3
101.1
30.8
68
101.1
33.1
0.464
68.1
57%
574
524
685
644
0.323
0.363
7.1
0.383
258.6
230.3
11.0%
78.1
101.1
23.0
76
101.1
25.1
0.451
75.9
69%
689
629
792
742
0.335
0.366
8.3
0.391
249.2
227.9
8.5%
1.2
0.8333
12
85.6
101.1
15.5
83
101.1
18.1
0.430
83.3
80%
804
734
899
841
0.344
0.360
9.4
0.402
242.6
231.8
4.4%
1.2
0.8333
12
95.3
101.1
5.8
95
101.1
6.1
0.430
95.0
100%
1000
913
1086
1011
0.355
0.373
11.4
0.414
235.4
223.8
4.9%
95