APPLIED THERMODYNAMICS & THERMAL ENGIN..PREVIOUS Q.PAPERS

Posted on Thursday, 14 May 2015


APPLIED THERMODYNAMICS & THERMAL ENGIN..PREVIOUS Q.PAPERS










II B.TECH - II SEMESTER EXAMINATIONS, APRIL/MAY, 2011



APPLIED THERMODYNAMICS – I



Time: 3hours
(MECHANICAL ENGINEERING)
Max. Marks: 75


Answer any FIVE questions







All Questions Carry Equal Marks




- - -




1.a)      Derive the equation for efficiency of diesel cycle.

b)            A four stroke diesel engine has a bore of 25 cm and stroke of 40 cm. Cut off takes place at 8% of the stroke and initial pressure of the cycle is 0.1 MPa. Calculate the air

standard efficiency, m.e.p. and power developed by the engine if it is running at


400 rpm.
[7+8]
2.a)
With the help of a line diagram, explain the fuel atomizer.

b)
Differentiate between indicator diagram and valve timing diagram.
[7+8]

3.                  With all minute details, explain the factors affecting the knocking including the fuel


characteristics for S I Engines and C I Engines.
[15]
4.a)
With the help of diagrams, explain different combustion chambers used in CI engines

and advantages of each.

b)
What is meant by delay period and explain factors affecting the delay period.
[8+7]

5.a)      Derive an equation for the work done in single stage reciprocating compressor neglecting the clearance volume.

b)            Air at 1 bar and 270C is taken into single stage single acting reciprocating air compressor with law of pv1.1 = constant to a final pressure of 7 bar and compressor takes 1 m3/min. Calculate the indicated power and isothermal efficiency. Also calculate the cylinder dimensions and power of the motor required to drive compressor. Speed of compressor is 5 rps. Stroke to bore ratio 1.5:1, ηmech = 85%,

ηtransmission  = 90%.[7+8]

6.                  A 4 cylinder 4 – stroke petrol engine having bore 6 cm and stroke 10 cm develops 65 N-m torque at 3000 RPM. Find the fuel consumption of the engine in kg/hr and brake mean effective pressure, if the relative efficiency of 50% and clearance volume

is 60 cm3. Take CV = 40 MJ/kg.
[15]

7.a)      Explain the working details of steady flow rotary compressors and p – v curves of the same.

b)            Derive the equation for the thermodynamics cycle work done for a rotary compressor.
[8+7]
8.
Write short notes:


a) Fuel rating methods.


b) p-θ diagrams in Engine testing.


c) Velocity triangles for axial flow compressor.
[15]


********




No comments:

Post a Comment

2015 © JNTU Kicks » JNTU Fast Updates,JNTU News,JNTU Results - All Rights Reserved. | Designed By Rkc