AER710PropulsionIntro1

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AER 710 Aerospace Propulsion
Instructor: Dr. David R. Greatrix
Dept. of Aerospace Engineering
Ryerson University
Email: greatrix@ryerson.ca
Phone: ext. 6432
Office: ENG 145
Counselling hours: posted
Teaching Assistants
• Sections 1 & 2:
Arthur Lin, a2lin@ryerson.ca
• Sections 3 &4:
Daniel Finistauri, dfinista@ryerson.ca
Additonal Logistics
• Lectures in ENG 102, Wed., 2 pm – 4 pm
ENG 106, Fri., 9 am – 10 am
• Labs: experimental air rocket and turbojet performance
evaluation (KHE 21), schedule will be announced on
Blackboard ; possible additional hardware demos to be
done as well, if time allows
• In remaining available lab hours of the semester, tutorial
problems, project advice, etc., covered in lab hours by
teaching assistant :
Mon., 12-1 EPH 105 Sct. 4
Tues., 12-1 EPH 105 Sct. 2
Fri., 12-1 POD 361 Sct. 3
Fri., 1-2 KHE 118A Sct. 1
Logistics (cont’d)
- counselling hours posted on my door (Tues. 9-10; Wed.,
1-2; Fri., 10-11), but I’m flexible; phone/email me ahead
of time, or come by my office (ENG 145), and if I’m
available, I’ll see you
• Evaluation:
Fri., Mar. 2, 9 am
Univ. will sched. in April
1 Indiv. Proj. Report 15%
2 Group Lab Reports 10%
1 Term Test, 50 min. 25%
Final Exam, 3 hr. 50%
• No official course textbook; recommended books are
useful for project and filling in gaps in understanding
• Tests are open lecture notes + practice problem/soln. set
+ regular calculator
Logistics (cont’d)
• Tests: partial marks for logical procedure
shown + for correct interim values
• Project may involve computer
programming and/or spreadsheet analysis,
at your discretion
• Zero marks for late project and lab report
submissions
Logistics (cont’d)
• For hardware lab groups, will allow for
self-selection for people in the same
section up to the deadline of noon, Fri.,
Jan. 20. Maximum of 4 in proposed
groups. After that, I’ll place remaining
students into existing or new groups, as
required.
• Hardware lab reports are due one week
later, by 4 pm, in my drop box
Outline of Course:
Introduction
Propellers
Internal Combustion Engines
Gas Turbine Engines
Chemical Rockets
Non-Chemical Space Propulsion Systems
Wright Flyer I
Delta II
Introduction to Aerospace Propulsion
• The course will cover in varying degrees of
detail the variety of aerospace propulsion
systems that have been developed over the
last 100+ years
• Most of the course will focus on gas turbine
engines (turbojets, turbofans, turboprops,
turboshafts), as is traditional for an
undergraduate propulsion course
• Let’s review some useful information, before
getting into details on specific systems
Design Issues
• From past courses like Flight Mechanics and
Aircraft Performance, one understands the
importance of thrust delivery for meeting critical
flight mission elements, e.g., high thrust for
takeoff for fixed-wing airplanes, medium to low
thrust for economic cruise at altitude
• Flight vehicle performance guidelines help to
dictate propulsion system expectations, e.g.,
max. static thrust to weight (F/W) of 0.3 to 0.4 for
conventional fixed-wing airplanes
Design and Certification
• For conventional propulsion system
development, one would progress from
concept introduction, to preliminary design,
to advanced design, to prototype
building/testing, to certification
• The country’s transport authority (Transport
Canada) will evaluate the propulsion
system’s compliance with the established
regulations in regards to safety,
performance, manufacturing, etc., before
granting a type certificate that allows for
general production of that system
Integration of the Propulsion System to the Flight Vehicle
• The given propulsion system will need to be
integrated to the flight vehicle that is was
designed for, and the resulting performance
of the flight vehicle should meet or exceed
expectations for the overall process to be
considered successful
• For example, in the case of turbofan
engines, for easier maintenance, cleaner
aerodynamics, etc., one commonly sees a
pod-mounted approach for mating the
engine to the wing and/or fuselage of a
commercial transport airplane:
Rolls-Royce Trent 900 turbofan
• Sometimes, the integration can be a bit
more complicated:
DC-10
L-1011
F-15
P&W F100 low-bypass turbofan
Quick Thermodynamics Review
p
T
M
 RT 
RT
v
h  CvT  RT  (Cv  R)T  C pT
 
Cp
Cv

Cp
Cp  R

1
R
1
Cp
p
a  RT 

Ma 
V
a
, ideal gas equation
of state
, enthalpy of gas
, ratio of specific heats
, speed of sound in gas
, flow Mach number
Isentropic Flow
 1
p2  

T2 
 
T1  p1 
1
 2  p 2   v1
 
 
1  p1 
v2
T2  2  (  1) Ma12 


2
T1  2  (  1) Ma2 
 1
 1) Ma 2  2( 1)
A1 Ma2  2  (
1



A2 Ma1  2  (  1) Ma22 
Combustion
• Most of the higher performance propulsion
systems that will be looked at in this
course will be using chemical combustion
as the means for generating heat energy,
energy that will ultimately be converted
into the delivery of thrust via mechanical
rotation (propeller, fan) or exhausting a
high-speed jet
• Alternatives to the combustion approach
exist, for some flight applications
Combustion: Flame Structure
• Heat released (and chemical combustion products
produced) when fuel molecules come together and react
with oxidizer molecules above a threshold (auto-ignition)
temperature
• Premixed laminar flame, first category; process of
combustion is driven predominantly by pressure
• Turbulent diffusion flame, second category; process of
combustion is driven predominantly by mixing
• Commonly in propulsion system combustors, flame is a
combination of the above two
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