Applied Thermodynamics - II, Question Paper of Mechanical Engineering 4th Semester, Download Question Paper Applied Thermodynamics 5

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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

l. Write short notes on :

(a) What is pre ignition ?

(b) What is centane number ?

(c) Explain the term supercharging.

(d) What do you mean by surging & choking ?

(e) Define degree of reaction for axial flow compressors.

(f) Explain the term pre whirl.

(g) Enumerate the various uses of gas turbines.

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

(i) Write the name of two solid propellants.

(j) What are the advantages of multi-stage compression?

SECTION-B

2. Explain the phenomenon of knock in Combustion Ignition Engine &

compare it with SI engine knock.

3. Explain the function of impeller & diffuser used in a centrifugal compressor.

4. Show that axial flow compressor with 50% reaction has symmetrical

bladings.

5. Explain the fundamental difference between the Jet propulsion & Rocket

propulsion.

6. State the merits & demerits of closed cycle gas turbine over open cycle

gas turbine.

SECTION-C

7. (a) What is delay period and what are the factors that affect the delay

period ?

(b) What are the various characteristics of an efficient cooling system ?

8. In a gas turbine plant working on the Pnayton cycle with a regenerator of

75% effectiveness, the air at the inlet to the compressor is at 1 bar,

30°C, the pressure ratio is 6 and the maximum cycle temperature is

900°C. If the turbine and compressor have each an efficiency of 80%,

find the percentage increase in cycle efficiency due to regeneration.

9. A centrifugal compressor has an inlet eye 150 mm diameter. The impeller

revolves at 20,000 rpm and the inlet air has an axial velocity of 107 m/s,

inlet stagnation temperature 294 K and inlet pressure 1·03 bar. Determine:

(a) Theoretical angle of the blade at this points and

(b) Mach number of the flow at the tip of the eye.