Propulsion Systems
Objectives
- Present the classification of aircraft and aircraft propulsion systems, its early history, innovative breakthroughs, and current aircraft engine improvement challenges for sustainable aviation.
- Provide the most relevant aerothermodynamics principles for jet engine propulsion.
- Calculate engine thrust and relevant engine performance parameters.
- Provide a through treatment and understanding of the classical aircraft engine cycles (foundation of aircraft propulsion).
- Introduce advanced concepts in airbreathing propulsion.
- Introduce chemical rocket and hypersonic propulsion.
General characterization
Code
13142
Credits
6.0
Responsible teacher
Jorge Emanuel Pereira Navalho, Luís Miguel Chagas da Costa Gil
Hours
Weekly - 4
Total - 50
Teaching language
Inglês
Prerequisites
Background in thermodynamics, fluid mechanics, and heat transfer at a fundamental level is recommended but not mandatory.
Bibliography
- Saeed Farokhi, “Aircraft propulsion: cleaner, learner, and greener”. John Wiley & Sons, 3rd edition, 2022.
- Ahmed F. El-Sayed, “Aircraft propulsion and gas turbine engines”, 2ndedition, 2017.
- Ahmed F. El-Sayed, “Fundamentals of aircraft and rocket propulsion”. Springer, 1st edition, 2016.
- George P. Sutton and Oscar Biblarz, “Rocket propulsion elements”. John Wiley & Sons, 9th edition, 2016.
- Rolls Royce, “The jet engine”, Wiley, 5th Edition, 2015.
- Frank M. White and Henry Xue, “Fluid eechanics”. McGraw-Hill, 9th Edition, 2021.
- Michael J. Moran and Howard N. Shapiro, "Fundamentals of engineering thermodynamics", John Wiley & Sons, 5th edition, 2006.
Teaching method
The presentation of the syllabus of the curricular unit is done in theoretical-practical classes. After exposing the theoretical concepts, the professor proposes to the students the resolution and subsequent discussion of practical application problems. In addition to the theoretical-practical classes, students (organized into groups) carry out a comprehensive literature investigation (with ensuing presentation and discussion) on specific and promising concepts on sustainable aircraft propulsion.
Evaluation method
The assessment in this curricular unit takes into account the following:
- 2 tests or 1 final exam; and
- 1 assignment on a specific topic on sustainable aircraft propulsion.
The final mark calculation (FM) is given by one of the following weighted averages which involve the mark of Test 1 (MT1), mark of Test 2 (MT2), the mark of the Final Exam (MFE) and the mark of the Assignment (MA) — the values are rounded to one decimal place:
FM=MAX[(0.45MT1+0.35MT2+0.20MA),(0.80MFE+0.20MA)]
To be approved at this curricular unit the student must verify the following criteria:
- deliver, present, and discuss a report related to the assignment which should have a mark (MA) ≥ 8.0 val.; and
- obtain a final mark (FM) ≥ 9.5 val.
Final marks higher or equal to 17 val. can be subjected to an oral examination.
Additional information and general rules for written evaluations:
- Written evaluation (tests and exams) are closed book. Any formulae, chart, or table required will be provided at the evaluation statement.
- During the evaluation it is strictly forbidden the utilization of: (1) calculators with text storage capacity; (2) smartphones; (3) smartwatches; (4) any mean or device that allows data storage; (5) any mean or device that allows communication with other person or resource inside or outside the room where the evaluation is conducted. Transgressions are subjected to the RAC.
- Only pen-answered questions are accepted.
- Students should make use of a classic watch (watch without any data storage capacity) to control the available time.
- Students must register for the tests and exams during the corresponding time frames.
Subject matter
- Introduction to aircraft propulsion. Definition and classification of aircraft and propulsion systems; brief and early history of aviation and aircraft propulsion; innovative breakthroughs in gas turbine propulsion; aviation impact on the environment and sustainable aviation.
- Compressible flow. Revision of thermodynamics; speed of sound; adiabatic and isentropic steady flow; isentropic quasi-one-dimensional flow; normal shock wave; oblique shock wave; conical shocks; Prandtl-Meyer expansion waves; fluid impulse.
- Engine thrust and performance parameters. Rigorous derivations of uninstalled thrust and installation effects; airbreathing engine performance parameters: specific thrust, specific fuel consumption and impulse, thermal, propulsive and overall efficiency, and impact of engine overall efficiency on aircraft range and endurance; performance characteristics of modern aircraft engines.
- Analysis of aircraft gas turbine engine cycles. Turbojet engine; turbojet engine with an afterburner; turbofan engine; ultra-high bypass turbofan engine with an afterburner; separate-exhaust and mixed-exhaust turbofan engines; and turboprop engines; propeller theory (actuator disk); description of real and ideal behaviors of engine components; physical and mathematical definition of efficiencies, losses, and other performance parameters for each engine component; calculation of engine performance parameters, viz. specific thrust, specific fuel consumption and thermal, propulsive, and overall efficiencies; promising propulsion and power technologies in sustainable aviation.
- Rocket and hypersonic propulsion. Chemical rockets: liquid, solid, gaseous, and hybrid propellant rockets. Chemical rocket applications. Rocket propulsion parameters, thrust coefficient, characteristic velocity, propulsive and overall efficiency.