Cochin University of Science and Techology (CUST) 2006 B.Tech Civil Engineering Mechanical Engineering I - Question Paper

B. Tech Degree I & II Semester (Combined) Examination June 2006

IT/CS/EC/CE/ME/SE/EI/EB/EE/MRE 1 07

fundamentals of engineering i

(Common)

(b) MECHANICAL ENGINEERING

Time : 1 Vi Hours    Maximum Marks : 50

I.    (a) Derive an expression for work done in an adiabatic process.    (7) (b) A closed vessel containing 2 Kg. of carbon dioxide is at a temperature 20C and

pressure Qf 0.7 bar. Heat s supplied to the vessel till the ga i acquires a pressure of 1.4 bar. Calculate -

(1) Final temperature    (2) Work done on or by the gas

(3) Heat added    (4) Change in internal energy.

Take specific heat of the g as at constant volume as 0.657 K, /Kg K.    (10)

OR

II.    (a) Explain the Kelvin - Plan;k and Clausius statements of the >econd law of thermo

dynamics and prove their jquivalence.    (9)

(b) A camot heat engine receives 500 KJ of heat per cycle from a high temperature source at 652C and rejects heat to a low temperature sink at 30C. Determine the camot efficiency and the amount of heat rejected to the sink per cycle.    (8)

III.    (a) Derive an expression for the air standard efficiency of Diesel cycle.    (9) (b) An engine working on the otto cycle has a cylinder diameter of 150 mm and stroke of

225 mm. The clearance volume is 1.25 x 10~³ m³. Find the air standard efficiency.

Take / = 1.4.    (8)

OR

IV.    (a) Explain the working of a lour stroke, C.I. engine with a nea sketch.    (8) (b) Explain with the help of a neat sketch, a plain carburattor showing idling jet and choke.

What is the function of choke?    (9)

V.    (a) Explain the terms:

(i) Saturation temperature    (ii) Wet steam

(iii) Super heated steam    (iv) Dryness fraction.    (8)

(b) Explain the working of a Uabcock and W ilcox water tube b oiler with a neat sketch.    (8)

OR

VI.    (a) Explain difference between impulse turbine and reaction turbine,    (8)

(b) Explain the term compounding in steam turbines. Discuss various methods of

compounding steam turbhes.    (8)

Attachment: cochin-university-of-science-and-techology--cust--2006-b-tech-civil-engineering-36796-1.pdf

Earning:   Approval pending.