Prof. L.M.Das
Centre for Energy studies,
Indian Institute of Technology Delhi
Dr. Mathew Abraham
Senior General Manager
Mahindra and Mahindra Ltd

•
Introduction
• Advantages and limitations with Hydrogen operation
• R&D Pursuits and attainments in IIT Delhi
• Mission Mode Project
•
Research activities


High Thermal Efficiency


Energy Content
– LHV: H
2
=120 MJ/kg;
– Gasoline=43 MJ/kg
Very tunable combustion
LFL/UFL(Vol%):
- H
2
=4/75
- Gasoline =1/7.6

Near Zero Emissions
Smooth Engine operation

Lower NOx Emission at 0.4<

< 0.6
Reference: L.M.Das, Exhaust E mission Characterization of Hydrogen-
Operated Engine System: Nature of Pollutants and Their Control Techniques,
Int. J. Hydrogen Energy Vol. 16, No. 11, pp. 765-775, 1991.

Low

Reduced power output due to the low heating value on volume basis

Needs 40-60% larger size than for gasoline for same power and speed.

High NO
X
at higher loads

Rapid Rate of Pressure Rise

Knocking
SURFACE
IGNITION
PRE-IGNITION
Backfiring OR
Back-flash
Engine ‘‘knock’’
• Uncontrolled ignition induced by a hot spot
• Occurring during the compression stroke with the actual start of combustion prior to spark timing
• Hydrogen–air charge combusts in an intake runner or intake manifold
• Autoignition of the remaining endgas with high-pressure oscillations and the typical pinging noise
Direct Injection
Stratification is possible
& high operation pressure 5–250 bar
Timed Injection
High
Carburetion
External mixture formation : operated at lower injection pressures
Example of reduced power output (Sopena et. al.
(2010))
6

Stable engine operation range

Range of equivalence ratio in lean burn mode
 Unstable engine operation near stoichiometric condition
 Combustion instability & reduction in thermal η has been reported for

<0.4
Strategies to Control the Backfire, Knocking & NOX
 Injection of cooled exhaust gases into cylinder
 Injection of water into cylinder
 leaner operation
 Timed Manifold Injection Technique
 Optimizing start of injection, duration & timings
Strategies to Increase the power output
 By Turbo-charging /supercharging
 By increasing the compression ratio
 By suitable fuel induction method
 By optimizing Injection duration & ignition timings
7

HYDRAULICALLY OPERATED
INJECTION SYSTEM
CAM-ACTUATED INJECTION SYSTEM
Neat Hydrogen-fuelled
S.I. Engine Genset
TOTAL HYDROGEN S.I. ENGINE
GENSET USING ELECTRONIC FUEL
INJECTION SYSTEM
SIX CYLINDER HYDROGEN –
DIESEL DUAL ENGINE GENSET
– (Ashok Leyland Engine )
HYDROGEN FUELLED DIESEL
ENGINE

Official inauguration was held on 9 th January 2012 in Pragati
Maidan, New Delhi

Indian Institute of Technology Delhi
Mahindra and Mahindra
1) Coordinating
2) Optimization of the engine for better performance and emissions without any symptoms of undesirable combustion phenomena
3) Dissemination
1) Providing two vehicles (4 cylinder
Engine)
2) Engine Controller Development
3) Components developments,
Engine and vehicle integration
4) Field trials
13

Broad Objectives:
 To develop an optimum hydrogen fuelled engine and demonstrate it on mass transport vehicle by testing, field evaluation and demonstration trials.
Specific objectives:
 To focus on development of hydrogen gas fuelled multi cylinder internal combustion engine for mass transport vehicle.
 To develop two mini bus vehicle for demonstration and field trials.
 To evaluate performance & durability, assess cost of the technologies and address system engineering issues.
 To provide information on the status of the technology.
14

 Scope
◦ Develop 4 Cylinder Engine to operate on Hydrogen high efficiency, low emission with all safety system.
◦ Demonstration on 2 Mahindra minibus with the developed engine
 The entire project shall be executed in two phases:
◦ Phase I involves engineering and system development of the
Hydrogen system covers testing, optimization at engine level;
◦ Phase II for evaluation to integrate on vehicle for demonstration and validation.

Fuel
Stroke (mm)
CNG Hydrogen
88.89 88.89
Bore(mm)
No. of Cyl
Power (kW)@speed
(rpm)
100.3
4
56@3200 &
70@3600
Torque(Nm)@ speed(rpm)
220@1800-2200
Compression Ratio 11
100.3
4
*60 -65 @3600
*190@1800-2200
12
Air induction Turbocharged (air cooled)
Turbocharged
(water cooled
Bearing, recirculation valve,vacuum type waste gate actuation
*
Predicted performance with Boost will be decided based on backfire control after engine testing

Thermodynamic & fluid dynamic simulations
Simulation is done using AVL Boost Simulation and flow analysis through CFD where performed by Mahindra.
Components development
Development of Proto Components like Piston, Intake & Exhaust manifold, Turbocharger etc. was developed by M&M.
Selection & development of Hydrogen Compatible components like Cylinders, Sensors, fuel
Injector, wiring harness etc. To be done
Controller development
Development of Controller & necessary software for Hydrogen operation is ongoing
Engine testing
Testing at IIT for Data Collection and Optimization of the Engine. Final development & calibration of Engine to Meet the power and torque requirement also the emissions norms.
Vehicle build for demo
Development of two minibuses and the necessary conversion, vehicle calibration and do field trials for 1 lakh kms will be done after engine development

Flow estimation
Due to double stoichiometric air fuel ratio, air flow rate & Boost pressure drastically varies and it requires modification in the existing turbocharger. Hence a new turbocharger was developed with following features;
Vacuum Operated Waste gate actuation mechanism, water cooled bearing housing, Electrically operated Dump valve.
Ignition system development
Hydrogen requires low ignition energy of 0.02 mJ compared to the gasoline/CNG systems. Hence a development of low energy
Iridium spark plug, Ignition coils are necessary to avoid preignition, abnormal combustion.

Injection system development
The existing injectors are not suitable for hydrogen operations due to leakage, high wear and tear, lubricity issues. Hence for hydrogen operations dedicated hydrogen injectors are required to meet the required flow rate. It involves the development of injectors, gas rail assembly, metered pressure regulator.
Throttle body development
The existing throttle body is having limitations with respect to flow rates require different throttle body to accommodate hydrogen flow rate conditions
Controller development
Hydrogen engine requires new controller development which should have different maps for optimizing timings, flow rates, injection pressures, idle control, startability, safety controls etc

The existing lambda sensor is designed of HC fuel’s air fuel ratio range. For hydrogen fuel to operate from 4 -75 % of air requires wide band Lambda sensor for operating in lean mixture. To meet the required emissions the hydrogen requires different operating air fuel ratios for its operations
Due to increased flow quantity, a separate exhaust manifold has to be developed to accommodate the new turbocharger.

• Hydrogen Sensors
– Placed near storage tank, engine compartment with passive and active ventilation
• Hydrogen Safety Controller
– If leakage is sensed, the hydrogen supply is cut off with a solenoid valve
• Flame arrestor
– In case of backfire, it stops the flame from traveling towards the source of hydrogen
• Carbon fibre tanks
– Aluminum tank wrapped in carbon fibre – Carbon Steel not suitable due to
Hydrogen embrittlement
Hydrogen
Sensor
Hydrogen Cylinder
Pressure
Regulator
Gas
Solenoid
Quarter
Turn Valve
ECU
Flame
Arrestor
Injector

Thermodynamic Simulation
Boost Simulation Model

AVL Boost Simulation – Results and Discussion
Cylinder Pressure History at 3600 rpm (Predicted)
It is observed from the Figure 13 that the peak firing pressure of 84.73 bar obtained at 3600 rpm and the peak firing pressure occurred at a crank angle of 12.77 deg ATDC. These Pressure Crank angle data further need to be validated during IIT Delhi Testing
23

Compression Ratio Finalization based on the Required RON(Research Octane Number) prediction
Speed/CR 11 11.5 12 12.5 13 13.5 14
3600 112 115 118 125 125 129 132
3200
3000
2600
2200
115 120 124 129 130 133 137
117 121 125 131 132 135 139
116 121 124 131 132 135 139
117 120 124 133 134 136.5 140
1800
1400
1250
118 121.5 127 134 134 138 142
117 120 124 132 132 136 140
112 117 121 127 128 131 135
To be on the safer side i.e., to limit the Knocking – from the above table Compression ratio is considered as 12
(RON <130). This value of 12 Compression ratio will be taken as base for our Testing activities

AVL Boost Simulation – Results and Discussion
Predicted Power, Torque and BSFC
Speed RPM

IMEP, BMEP and FMEP(Predicted)
*Hydrogen Engine Performance predicted by Boost
The maximum BMEP which can be achieved at maximum torque speed is approximately around 10 bar at 1800 rpm
26

CFD Simulation
Objective: To Predict the chance of Backflow conditions of the Injected Gaseous Hydrogen on ports of the given Intake Manifold
CFD Model:
Inlet of Intake Manifold
Hydrogen Injections
Port 1
Port 2
Port 3
ENGINE SPECIFICATIONS
Cylinder Arrangement
No of Cylinders
Bore
Stroke
Engine Capacity
: Inline
: 4
: 89mm
: 100mm
: 2.4L
Injection System
Fuel
Compression Ratio
Power
Torque
: MPFI
: Gaseous H
2
: 12 : 1
: 66 kw
: 175 Nm
Port 4
Fig(a)
Boundary Conditions: For Engine Speed of 3600 RPM, the transient results obtained from AVL boost simulations are applied in this simulation. The transient data are plotted in the next slides.

CFD Simulation
Computation Model:
 CFD simulation was carried out on the given model of intake manifold with injector locations.
 Computational fluid dynamic modeling was developed utilizing
ANSA v 13.1.3 and T-Grid v5 preprocessing software.
 The mesh was created utilizing triangular for surfaces of the given 3D model.
 The developed CFD model of surface elements using ANSA preprocessing software.
 The surface mesh count is 0.164 million elements.
 T-Grid was used to generate tetrahedral cells with multiple domains.
 There are total of five volumes out of which four are for injectors and one for intake manifold. These four volume mesh are finer when compared with intake manifold volume mesh.
 The total cell count of all five volumes are 3.29 million cells.
28

CFD Simulation
Results:
Graph (d) shows the Total Mass Flow rate distribution to all cylinders . And the Mass Flow rate fluctuations at the inlet of the intake manifold is also graphed. The Maximum flow rate for the cylinders 1-2-3-4 are 300-350Kg/hr
Graph(e)
Graph (e) shows the Mass Fraction of Hydrogen which is entering into the Cylinders 1-2-3-4. The Values are face average of the outlets (i.e.
Cylinder Inlets). The Mass fraction in the cylinder 3 is less when compared to rest of the cylinders. But when we calculate the deviation or difference in percentage amongst the cylinders, it is found that the variation <2%
The sum of Total Mass Fraction of all cylinders from 0 to 720 degree comes to 2.83 , and percentage deviation is 25.5,25.5,23.5 & 26.
The Animation of the Fuel injection (H
2
) on all four injectors as per firing order and its movement with respect Valve openings for one complete revolution of 0-720 degrees CA are monitored and compiled as an animation in the next slide.

CFD Simulation
Results:
Animation (a)
Conclusion:
The analysis is carried out with the given AVL Boost Results as the boundary conditions and the Fuel (H
2 timing and the start and stop of H
2 flow of H
2 range between 0.01 to 0.03 which is also captured in the above animation.
) is injected as the per firing order. The Injection
is also used as boundary conditions with respect to Crank Angle. From the results, it is observed that there is no back
when we track 0.03 mass fraction that is for AFR of 34.3:1, and if the Actual fuel ratio is lean (i.e. >34.3 :1), the values will be falling in the

• Piston with 12/13 Compression Ratios were developed
• The Turbocharger has Vacuum Operated Wastegate actuation mechanism, water cooled bearing housing,
Electrically operated Dump valve
• Electronic Throttle Body DV-E5 was developed
• wide band lambda sensor
• New exhaust Manifold
• New Controller
31


Mission Mode
Project and Dual Fuel Project)
– IOCL Facility (awaiting for approvals)
– Only facility at Pragati Maidan - Set up by UNIDO: dedicated hydrogen dispensing station for DELHY-3W project- Uncertain unless project extended beyond Oct 2012.

– Approval for Storage tank only 200bar – Less mileage
– Approval for cylinders, valves and importing cylinder, filling approvals
– Vehicle standards for Hydrogen not available – Approval for test vehicles for trials

5 April 2011
36

9 August 2012
37

Phase I, Design , Fabrication and Testing of engine:
Task 01 : Component/System design & development
 This development task will involve reviewing the design targets and constraints established in the hydrogen project. Completed
 M&M and IIT-Delhi will revise these targets for hydrogen operation from existing CNG engine. Completed
 The base engine for hydrogen operations is derived from Mahindra CNG engine. Necessary design modifications for compression ratio, low energy spark plug etc. are developed by
Mahindra .
Design modification for Compression ratio, turbo charger completed and assembled two engines.
 The proto assembled engine will be tested at IIT-Delhi with initial calibration for performance/durability behavior. On going ( IIT Received the Dynamometer & engine. commissioning ongoing once completed the engine will be tested)
 The preliminary design targets are EURO-V emissions compliance on ETC cycle and less than
10 % power loss (80-85 hp) compared to baseline CNG operation (95 hp @ 3600 rpm, 170
Nm@2400 rpm) .

 Boost simulation for hydrogen engine specification is performed by M&M.-
Completed
 CFD Simulation for Hydrogen flow at Intake Manifold is performed by M&M -
Completed
 Based on the simulation done by Mahindra, IIT-Delhi will do the testing and validate for compression ratio, low energy spark plug etc.. This activity is initiated by both M&M and IIT Delhi.
 Provide layout drawing with packaging details of each components- Engine Level
Drawings are Completed and Vehicle level are partly completed
 Component/system selection – Completed
 Component/system packaging (inclusive of fuel rail with H2 injectors, pressure and temperature sensors on engine) – This will done at M&M with the packaging input from external agency. - Drawings received fabrication ongoing
 Provide 2D and 3D data – The details provided by external agency will be approved by M&M.Completed
 Wiring system design & development - In progress

Task 02 : Development of Requirement Specifications for Hydrogen Controllers
 This task will build on requirement specifications for design and development established in the hydrogen project by reviewing all functional specifications, operating guidelines, packaging constraints and targets, environmental specifications, and performance criteria for the INCA-based hydrogen controller. These task is Ongoing
 Also the controller must have CAN (Controlled Area Network) interface as it is required for interface with other systems of the vehicle. These task is Ongoing .
Task 03 : Control system design and the Software Development
 Hydrogen control strategies and algorithms will be developed and tested using the prototype discussed above in Task 01.
 Software design will also be influenced by the requirement specifications developed in Tasks 01 and 02. Matlab/Simulink control algorithms of will be shared as object blocks with M&M in an effort to advance the level of performance with hydrogen operation.
 The software will have provisions for extension to chassis dyno emissions norms and further emission norms.
 Above tasks are in progress jointly with external agency.
40

Task 04 : Proto parts development and proto model
 Hydrogen specific components are designed by M&M in-consult with IIT-Delhi as per the target requirements. The designed components are proto manufactured and proto engine will be build.
 Development of Piston for 12 Compression ratio based on Boost Prediction – Completed
 Development of Turbocharger based on Boost Prediction – Completed (To be tested)
 Electronic Throttle Body – Completed ( Electronic Throttle Bodies are received the Supplier based on the new design for the air flow requirement)
 Universal Lambda Sensor for Hydrogen application – Completed (Lambda sensor is finalized and adoption of universal lambda sensor is under progress)
 Development of New Exhaust Manifold – Ongoing
Task 05 : Testing of proto engine and optimization of engine data
 Assembly of Proto Engine for Testing at IIT –Delhi – Completed (One Engine assembly sent to IIT
Delhi, Testing needs to be done at IIT-Delhi)
 Hydrogen specific components are proto manufactured by Mahindra will be tested for performance/durability at IIT-Delhi as per the target requirements . In progress
 The designed components once freezed similar set of proto components and final proto engine will be build.
41

Task 06: Supply of development controllers
 One controller will be used for initial Engine development at IIT Delhi along with the wiring harness. These task is Ongoing.
Task07: Development of engine by M&M
 Develop engine testing with Third party controller for data collection and working parameter will be performed by M&M at IIT Delhi. Work Initiated
 Engine Build for external agency by M&M - Work completed and engine send to external agency and the engine installation is in progress.
Task08: Calibration and Verification tests for meeting the performance targets
 The essential list of data's will be used for calibration and optimization of the parameters for hydrogen operation. Perform the verification test on the engine at test facility has the transient emission- ETC cycle capable to meet the required Euro V emissions (NOx only) on ETC cycle with
OBD, fuel efficiency, and performance over a wide range of speeds, loads, substitution rates, and injection timing strategies. To be initiated
42

Task 09: Joint Optimization
 M&M will do joint optimization with IIT to put effort to advance the level of performance on
Hydrogen operation. Along with software upgrades, control logics. To be initiated
Phase II, Packaging & Demonstration of Vehicle Development :
Task 10: Packaging
 Based on the testing, and the design targets established, there will be a refine in hydrogen operation for the Project Vehicles. The technical details for the system/components packaging in the vehicle will be developed. Third party consultation will be done for design review of the final build vehicle for fuel system leak, safety systems etc. initiated and the CAD modeling ongoing.
Task 11: Vehicle controller
 Based on Final calibration data and engine test data the vehicle controller with OBD will be developed in consultation with Quantum for usage in the Project Vehicles application to meet the required emission and best effort performance targets. To be initiated
Task 12: Retrofitting of two Hydrogen Minibus in India and demonstration
 M&M will retrofit two Minibuses (Project Vehicles) in India including the installation and integration of the Hydrogen storage and delivery system, and also the installation of the wiring harness, electronic controller, and user interface for the field demonstration of 2 Project
Vehicles in India for 1 lakh (100k) km. Vehicle capitalization is ongoing


