1. MEL 341 : GAS DYNAMICS & PROPULSION
P M V Subbarao
Professor
Mechanical Engineering Department
We learn this course as Gas dynamics for Propulsion

2. Course Overview
This undergraduate level course teaches the principles of jet propulsion.
The primary focus of the course is on the teaching of thermodynamics and Gas dynamics in aircraft engines.
The course provides information that will enable the engineering analysis of
ramjets and turbine engines and
its separate components including inlets, nozzles, combustion chambers, compressors, and turbines.

3. Course Objectives Students successfully completing MEL 341 will get:
A basic understanding of thermodynamic cycles of jet engines.
A basic understanding of the compressible fluid flow in inlets and compressors and turbines.
A basic understanding of the combustion physics in combustion chambers.
A basic understanding of the rational behind several types of jet engines.
The ability to analyze jet engines; determine propulsion efficiency and design inlets and nozzles.

4. Course Contents UNIT- I: Propulsion
 Aircraft Propulsion – introduction -- Early aircraft engines -- Types of aircraft engines -- Reciprocating internal combustion engines -- Gas turbine engines -- Turbo jet engine -- Turbo fan engine -- Turbo-prop engine
Aircraft propulsion theory: thrust, thrust power, propulsive and overall efficiencies -- Problems.
 UNIT- II: THERMODYNAMIC ANALYSIS OF IDEAL PROPULSION CYCLES
 Thermodynamic analysis of turbojet engine – Study of subsonic and supersonic engine models -- Identification and Selection of optimal operational parameters. Need for further development – Analysis of Turbojet with after burner.

5. Thermodynamic analysis of turbofan engine – Study of subsonic and supersonic systems -- Identification and selection of optimal operational parameters. Design of fuel efficient engines – Mixed flow turbo fan engine – Analysis of Turbofan with after burner.
Thermodynamic analysis of turbo-prop engine – Identification and selection of optimal operational parameters.

6. UNIT –III: GAS DYNAMICS OF PASSIVE COMPONENTS OF TURBO ENGINES
FUNDAMENTALS OF GAS DYNAMICS : Energy equation for a non-flow process -- Energy equation for a flow process -- The adiabatic energy equation -- Momentum Equation --Moment of Momentum equation -- Stagnation Velocity of Sound --Stagnation Pressure -- Stagnation Density -- Stagnation State -- Velocity of sound -- Critical states -- Mach number -- Critical Mach number -- Various regions of flow.
ANALYSIS OF DIFFUSERS AND NOZZLES: Introduction – study of intakes for subsonic and supersonic engines -- Comparison of isentropic and adiabatic processes -- Mach number variation -- Area ratio as function of Mach numbers -- Impulse function -- Mass flow rates -- Flow through nozzles -- Flow through diffusers – Effect of friction -- Analysis of intakes for supersonic engines – intakes with normal shock – oblique shocks – Study of special supersonic nozzles and diffusers.

7. UNIT –IV: STUDY OF COMPRESSORS
Design and Analysis of compressors – Classification – analysis of centrifugal compressors – velocity triangles – design of impellers and diffusers – analysis of axial flow compressor – analysis of stage – characterization of stage – design of multistage axial flow compressor – Performances analysis of centrifugal and axial flow compressors.

8. UNIT –V: GAS DYNAMICS OF COMBUSTORS
 Stoichimetry of combustion – calculation air-fuel ratio – gas dynamics of combustors – thermal loading factors – design and selection of combustors.
 UNIT –VI: STUDY OF TURBINES
Concept of gas turbine – analysis of turbine stage – velocity triangles and characterization of blades and stages – Design of multistage axial flow turbine – Performance analysis of turbines.
 UNIT –VI: ADDITIONAL TOPICS
Thermodynamic analysis real turbo engine cycles – performance analysis and thermodynamic optimization.
 Introduction to ramjets – study of rocket engines – study of missile engines.

9. Books & References Jet Propulsion:
Flack, R.D.., “Fundamentals of Jet Propulsion”, Cambridge University Press, 2005.
Baskharone, E.A., “Principles of Turbomachinery in Air-Breathing Engines”, Cambridge University Press, 2006.
Kerrebrock J.L., “Aircraft Engines and Gas Turbines”, MIT Press, 1992.
Mattingly, J.D., “Elements of Gas Turbine Propulsion”, McGraw-Hill Inc., 1996.
Gas Dynamics:
Anderson, J.D., “Modern Compressible Flow: With Historical Perspective”, McGrawHill, 2002.
Zuker, R.D., and Biblarz, O.,”Fundamentals of Gas Dynamics”, John Wiley & Sons Inc., 2002.
Thompson, P. A. Compressible Fluid Dynamics. Maple Press Company, 1984.
Saad, M.A.,”Compressible Fluid Flow”, Prentice-Hall, 1993.
Liepmann, H., and A. Roshko. Elements of Gas Dynamics. John Wiley Publishers, 1957.