Applied Thermodynamics - II, Question Paper of Mechanical Engineering 4th Semester, Download Question Paper Applied Thermodynamics 8

Roll No.

B. TECH (IE, ME) (Sem.-4th)

APPLIED THERMODYNAMICS-II

Subject Code: BTEE 404

Paper ID: [A1214]

Time: 3 Hrs.

INSTRUCTIONS TO CANDIDATE:

1.     Section A is compulsory consisting of ten questions carrying two marks each

2.     Section-B contains five questions carrying five marks each and st6u8dents have to attempt any four questions

3.     Section –C contains three question carrying ten marks each and students have to attempt any two questions

1.       

a.     What is cycle air rate.

b.     Define co- efficient of lift and drag

c.      What is degree of reaction.

d.     Define Stagnation pressure

e.      Define optimum pressure ratio.

f.       What is thermal efficiently?

g.     Explain the principle of jet propulsion

h.     Define ‘Best value of index.

i.       What is necessity of inter- cooling in compressor?

j.       Explain the working of vane type blower.

Section –B

2.     Derive the expression for the volumetric efficiently of a reciprocating air compressor in terms of clearance ratio, pressure ratio and index of the compression.

3.     A three stage compressor takes in air at rate of 0.25 m3/s at 1 bar and 298K. the pressure and temperature before compression is 1 bar and 308 K and the index of compression is 1.25. find inter cooler pressures and the minimum power required to run the  compressor, if the delivery pressure is 35 bar. Neglect the clearance.

4.     A centrifugal compressor receive air at 1 bar and delivers it at 3.5 bar. Find the final temperature of air if the initial temperature of air is 310K. the compressor compresses 2 kg of air per second.

5.     Derive the expression for the pressure ratio in each stage of multi stage axial flow air compressor

6.     Derive an expression for the optimum pressure ratio, for the maximum net work output, in a Brayton cycle. What is the corresponding cycle efficiency?  

7.     An axial flow compressor, with compression ratio as 4 , draws air at 20 C and delivers it at 197 C the mean blade speed and flow velocity are constant throughout the compressor. Assuming 50 % reaction blading and taking blade velocity as 180 m/s, find the flow velocity and the number of stages if work factor = 0.85, a = 2 B= 2 and Cp = 1.005 kj/kg K.

8.     A rotary air compressor working between 1 bar and 2.5 bar has internal and external diameter of impeller as 300 mm and 600 mm respectively. The vane angle at inlet and outlet are 30 and 45 respectively. If the air enters the impeller at 15 m/s find  i) speed of the impeeler in rpm ii) work done required by the compressor.

9.        

a.     Define thrust on a rocket. Derive an expression for the net thrust.

b.     Draw the neat sketch of liquid propellant engine and explain the general working.