Roll No. ......................
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 consisting of TEN questions
carrying
TWO marks each.
2. SECTION-B contains FIVE questions carrying FIVE marks
each and
students has to attempt any FOUR questions.
3. SECTION-C contains THREE questions carrying TEN marks
each and
students has to attempt any TWO questions.
SECTION-A
l. Answer briefly :
(a) What is delay period and what are the factors that
affect the delay
period ?
(b) What is the need of supercharging in I.C. Engines ?
(c) List the positive displacement type compressors of
rotary type.
(d) Define prewhirl. Explain its effect on the impeller of a
centrifugal
compressor.
(e) Explain the terms : mean effective pressure & swept
volume used in
case of internal combustion engines.
(f) Explain the terms slip factor and power input used in
case of centrifugal
compressor.
(g) What are the factors that affect the performance of
axial flow
compressor ?
(h) Write the field of applications of axial flow
compressors.
(i) Differentiate between closed & semi-closed gas
turbines.
(j) State the fundamental difference between the Jet
propulsion & Rocket
Propulsion
SECTION-B
2. Bring out clearly the process of combustion in C.I.
engines & also
explain the various stages of combustion.
3. Describe the phenomenon of detoriation in C.I. engines.
On what factors
does detoriation depend ?
4. Describe the function of impeller and diffuser in a
centrifugal compressor.
5. Draw the velocity triangles for hub, mean and tip radius
for free vortex
conditions.
6. Discuss briefly the methods employed for improvement of
thermal efficiency
of open cycle gas turbine plant.
SECTION-C
7. A gas turbine unit receives at 1 bar and 300 K and
compresses it
adiabatically to 6·2 bar with efficiency of the compressor
88%. The fuel
has a heating value of 44180 kJ/kg and the fuel/air ratio is
0·017 kg fuel/
kg air. The turbine internal efficiency is 90%, calculate
the compressor
work, turbine work and thermal efficiency.
8. Explain with neat sketch working of an Axial flow
compressor. How does
it differ from centrifugal compressor ?
9. A centrifugal compressor with an overall diameter of 1 m
runs at 5000
r.p.m. Air is supplied to the centrifugal compressor at 20°C
and 100 kPa.
The mass flow rate of air is 25 kg/s. Isentropic pressure
ratio is 2·5.
Calculate :
(a) Isentropic efficiency
(b) The rotor power
(c) The shaft power.
Assume slip factor of 0·9
0 comments:
Post a Comment
North India Campus