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