Name of the College : MAM School of Engineering
University : Anna University Chennai
Subject Code/Name : AE2254 – Propulsion I
Dept : AERONAUTICAL ENGINEERING
Degree : B.E
Year/Sem: II/IV
Website : mamse.co.in
Document Type : Question Bank
Download Model Question Paper : https://www.pdfquestion.in/uploads/mamse.co.in/3199-AE2255-qb.pdf
MAM Propulsion I Question Bank
PART A : (2 marks each)
UNIT I :
Fundamentals Of Gas Turbine Engines
** What are the methods of thrust augmentation ?
** Define by-pass ratio.
** Define propulsive efficiency.
Related : MAM School of Engineering AE2252 Aircraft systems and Instrumentation B.E Question Bank : www.pdfquestion.in/3198.html
** Write the thrust equation of a gas turbine engine.
** Draw the T-S diagram of gas turbine engine and the two important parameter of the cycle identity.
** Draw the variation of thrust with Mach number for different altitudes.
** What are the types of thrust ?
** List out the methods of thrust augmentation.
** What are the advantages of closed cycle gas turbine cycle ?
** Water injection at inlet of a gas turbine engine increases thrust. Comment on the statement.
UNIT II :
Subsonic And Supersonic Inlets For Jet Engines
** What is the effect of spring door in inlets ?
** Define spillage fraction.
** What is the prime requirement of an inlet ? List out the characteristics of supersonic and
** subsonic inlets.
** What is meant by sub-criticl mode of inlet operation ?
** What are the factors considered while designing a subsonic inlet ?
** State the phenomena of the stall in subsonic inlet.
** Differentiate between internal compression and external compression in a supersonic inlet.
** Define spillage fraction.
** List out the difference between subsonic and supersonic inlets.
** Draw T-S diagram for the inlet during low speed high thrust operation of a gas turbine engine.
** Differentiate between subcritical and supercritical modes of inlet operation.
** Define pattern factor. What is the desired range of this parameter ?
UNIT III :
Combustion Chambers
** Specific work output is 137 kJ/kg. Theoretical fuel air ratio is 0.0094. Combustion efficiency is
** 0.98. Find out specific fuel consumption.
** Name the flow losses in combustion chamber.
** What is the function of liners inside the combustion chamber ?
** Draw a stability curve of a combustion chamber and indicate the burning and non-burning zones.
** How flame stabilization is achieved in a combustion chamber ?
** List out the prime requirements of a combustion chamber.
** What is meant by stability loops ?
** What are the functions of dilution zone in combustion chamber of a gas turbine engine ?
UNIT IV :
Nozzles
What is meant by chocked nozzle ?
What are meant by underexpanded and overexpanded nozzles ?
What is meant by over-expanded nozzle.
Explain nozzle choking.
State at least two functions of a convergent nozzle.
What is thrust reversal ?
Define nozzle efficiency.
What are ejector nozzles ?
Define nozzle efficiency.
What is the need for variable area nozzle for supersonic operation ?
UNIT V :
Compressors
Distinguish between surging and stalling.
What is meant by prewhirl ?
What is the function of impeller in a centrifugal compressor ?
Define the phenomenon of surging of compressor.
What is the need for a prewhirl in a centrifugal compressor ?
Define the term degree of reaction.
What are the advantages of axial flow compressors over centrifugal compressors ?
Define degree of reaction.
What are the advantages of the axial flow compressor over the centrifugal flow compressor ?
Define degree of reaction of an axial flow compressor.
PART B : (16 marks each)
UNIT I
Fundamentals Of Gas Turbine Engines
(a) Define thrust of an engine and derive the thrust equation for a general propulsion system.
(b) Discuss the different methods of thrust augmentation. Draw T-S diagram for turbojet engine with thrust augmentation.
UNIT II
Subsonic And Supersonic Inlets For Jet Engines
(a) Explain successive steps in the acceleration and overspeeding of a one dimensional supersonic inlet with sketches.
(b) Derive the relation between area ratio Amax / Ai and external deceleration ration ui / ua.
(a) Explain starting problem in case of supersonic inlets. What is shock swallowing by area variation ?
(b) Explain the successive steps in the acceleration and over-speeding of a one dimensional supersonic inlet. (Fixed geometry convergent-divergent inlet).
UNIT III
Combustion Chambers
(a) What are the important factors affecting combusor design ?
(b) With a neat sketch explain the working of a combustion chamber.
(a) What are the three types of combustion chamber ? Compare its advantages and disadvantages.
(b) With the aid of a simplified picture explain the operation of a flame holder.
(a) With a neat sketch explain the various factors affecting combustion chamber design.
(b) Discuss in detail the various methods of flame stabilization.