AERONAUTICAL ENGINEERING


AIRCRAFT GAS TURBINE PROPULSION



 

UNIT I - FUNDAMENTALS OF GAS TURBINE ENGINES  

                       

Illustration of working of gas turbine engine – The thrust equation – Factors affecting thrust – Effect of pressure, velocity and temperature of air entering through gas turbine engines – Methods of thrust augmentation – Characteristics of turbojet, turboprop, turbofan, turbo shaft and ramjet – Performance Characteristics-Materials for gas turbine engines.



UNIT II - SUBSONIC AND SUPERSONIC INLETS      

                                 

Internal flow and Stall in subsonic inlets – Boundary layer separation – Major features of external flow near a subsonic inlet – Relation between minimum area ratio and external deceleration ratio – Diffuser performance – Supersonic inlets – Starting problem on supersonic inlets – Shock swallowing by area variation – External declaration – Models of inlet operation.



UNIT III – COMPRESSORS                  

                                                              

Principle of operation of axial and centrifugal compressor – Work done and pressure rise – Velocity diagrams – Diffuser vane design considerations – Concept of prewhirl – Rotation stall – Elementary theory of axial flow compressor – Velocity triangles – degree of reaction – Three 

dimensional – Air angle distributions for free vortex and constant reaction designs – Compressor blade design – Centrifugal and Axial compressor performance characteristics.



UNIT IV - COMBUSTION CHAMBERS AND NOZZLES 

                  

Classification of combustion chambers – Important factors affecting combustion chamber design – Combustion process – Combustion chamber performance – Effect of operating variables on performance – Flame tube cooling – Flame stabilization – Use of flame holders – simplex and Duplex type of Burners. Theory of flow in isentropic nozzles – Convergent nozzles and nozzle 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-Numerical problems



UNIT V - GAS TURBINES                                                                              


Impulse and reaction blading of gas turbines – Velocity triangles and power output – Elementary theory – Vortex theory – Choice of blade profile, pitch and chord – Estimation of stage performance – Limiting factors in gas turbine design- Overall turbine performance – Methods of blade cooling – Matching of turbine and compressor – Numerical problems.