Applied Thermodynamics - II, Question Paper of Mechanical Engineering 4th Semester, Download Question Paper Applied Thermodynamics 1

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Total No. of Questions : 09]

B. Tech. (Sem. – 4th)

APPLIED THERMODYNAMICS - II

SUBJECT CODE : ME – 208 (2008 Batch)

 Paper ID : [A0811]

Time : 03 Hours

Instruction to Candidates:

1) Section - A is Compulsory.

2) Attempt any Four questions from Section - B.

3) Attempt any Two questions from Section - C.

Section – A

Q1)

 a) How is compression ratio of an S.I. engine fixed?

 b) What is pre-ignition?

 c) Explain the term prewhirl used in centrifugal compressor.

 d) Define slip factor & pressure coefficient in the centrifugal compressor.

 e) Define degree of reaction.

 f) Explain the phenomenon of stalling in an axial flow compressor.

 g) State the assumptions made in an ideal cycle analysis of gas turbines.

 h) What is the difference between turbine blade and compressor blade.

 i) Define the term thrust and thrust power of jet propulsion system.

 j) Explain the principle of jet propulsion.

Section – B

Q2) Explain the effect of super charging of an I.C. Engine.

Q3) Explain the method to calculate the blade angle at the impeller eyeroot and the eye tip.

Q4) Explain briefly the design and off-design characteristics of an axial flow compressor.

Q5) Why are regenerators and intercoolers used in air craft engines?

Q6) Discuss the effect of compression ratio and air-fuel-ratio on the power and efficiency  of a petrol engine.

Section – C

Q7) The ambient conditions at inlet at 20ºC and 1 bar. At exit the total head temperature

and pressure are 150ºC and 3.5 bar, and static pressure at exit is 3 bar. Calculate

 (a) The Isentropic efficiency.

 (b) The polytropic efficiency.

 (c) The air velocity at exit.

Q8) In a gas turbine plant on the Brayton cycle the air at the inlet is 27ºC, 1 bar. The

pressure ratio is 6.25 and the maximum temperature is 800ºC. The turbine and

compressor efficiencies are each 80%. Find

 (a) The compressor work per kg of air.

 (b) The turbine work per kg of air.

 (c) The heat supplied per kg of air.

 (d) The cycle efficiency.

 (e) The turbine exhaust temperature.

Q9) (a) Explain the operation of a propeller. What is an athodyol? What is rocket.

(b) A turbojet flying at 850 km/hr has an air mass flow rate of 50 kg/s. The enthalpy

drop across the nozzle is 200 kJ/kg and the nozzle efficiency is 0.9. The air fuel

ratio is 80 and the heating value is 40 MJ/kg. Estimate the propulsive power,

thrust power, propulsive, thermal & overall efficiency of the unit.