JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

Pre-Requisites

Nil

Course Objectives:

• Analyse parametric cyclic analysis, performance parameters, efficiency, specific impulse of all air breathing engines.
• Know the design and performance of subsonic and supersonic inlets, types of combustion chambers and factors affecting the combustors.
• Discuss the types of nozzles, flow conditions in nozzles, interaction of nozzle flow with adjacent surfaces and thrust reversal
• Explain different types of compressors and turbines, work done, velocity diagrams and stage efficiency calculations.

Course Outcomes:

• Review the basic thermodynamic principles and fundamentals of gas turbine engines
• Outline the concepts of subsonic and supersonic inlets for jet engines
• Evaluate the operating characteristics of compressors and turbines in terms of blade shapes, angles, and direction of rotation
• Describe the fundamentals of combustion chamber, nozzle, ramjet and rocket propulsion

UNIT - I

Air-Breathing Engines Classes: Classification, operational envelopes; Description and function of gas generator, turbojet, turbofan, turboprop, turbo shaft, ramjet, scramjet, turbojet/ramjet combined cycle engine; Engine thrust, takeoff thrust, installed thrust, thrust equation; Engine performance parameters, specific thrust, specific fuel consumption and specific impulse, thermal efficiency, propulsive efficiency, engine overall efficiency and its impact on aircraft range and endurance; Engine cycle analysis and performance analysis for turbojet, turbojet with afterburner, turbofan engine, turboprop engine.

UNIT - II

Inlets And Combustion Chambers: Internal flow and stall in subsonic inlets, relation between minimum area ratio and eternal deceleration ratio, diffuser performance, supersonic inlets, starting problem on supersonic inlets, shock swallowing by area variation; Classification of combustion chambers, combustion chamber performance, effect of operating variables on performance, flame stabilization.

UNIT - III

Nozzles: Theory of flow in isentropic nozzles, nozzles and choking, nozzle throat conditions, nozzle efficiency, losses in nozzles. Over expanded and under expanded nozzles, ejector and variable area nozzles, interaction of nozzle flow with adjacent surfaces, thrust reversal.

UNIT - IV

Compressors: Principle of operation of centrifugal compressor and axial flow compressor, work done and pressure rise, velocity triangles, degree of reaction, free vortex and constant reaction designs of axial flow compressor, performance characteristics of centrifugal and axial flow compressors, stage efficiency calculations, cascade testing.

UNIT - V

Turbines: Principle of operation of axial flow turbines, limitations of radial flow turbines, work done and pressure rise, velocity triangles, degree of reaction, free vortex and constant angle designs,

R18 B.TECH AERONAUTICAL ENGG. III YEAR

performance characteristics, sample ramjet design calculations, flame stability problems in ramjet combustors, integral ram rockets.

TEXT BOOKS:

• 1. Hill, P.G. & Peterson, C.R. ―Mechanics & Thermodynamics of Propulsionǁ Addison Wesley Longman INC, 1999.
• 2. Mattingly J.D., ―Elements of Propulsion: Gas Turbines and Rocketǁ, AIAA, 1991.

REFERENCE BOOKS:

• 1. Cohen, H. Rogers, G. F.C. and Saravanamuttoo, H.I.H. ―Gas Turbine Theoryǁ, Longman, 1989.
• 2. Oates, G.C. - Aero thermodynamics of Aircraft Engine Componentsǁ, AIAA Education Series, New York, 1985. R18 B.TECH AERONAUTICAL ENGG. III YEAR