Osmania University (OU) 2007 B.E Electronics & Tele-Communication Engineering - Question Paper
Thursday, 04 July 2013 10:15Web
OSMANIA UNIVERSITY
ELEMENTS OF MECHANICAL ENGINEERING.
PART A:
1. Derive steady flow energy formula for an open flow with 1 inlet and 1 outlet?
2. explain with a neat sketch the value timing diagram of a petrol engine?
3. Write about the critical radius of insulation for cylinders?
4. Draw a sketch for the temperature variation of hot fluid and cold fluid during the flow through a parallel flw heat exchanger and write the LMTD expression?
5. Whatis the unit of refrigeration ? Explainhow it is defined?
6. describe wet bulb temperatue and relative humidity?
7. what do you understand by soldering and braxing ? why fluxes are used during soldering and brazing ?
8. Write short notes on sand casting?
9. Differentiate ranging from turning and shaping?
10. Derive an expression for the exact length of crossed belt?
PART B:
11. (a) provide thermodynamic definitionof work and heat with giving examples?
(b) An insulated cylinder of quantity capacity four mcube contains 20 kg of nitrogen. Paddle work is done on the gas by stirring it till the pressure in the vessel increases from four to eight bar. Take Cp = 1.04 kj/kg k and Cv = 0.74 kj/kg k. determine (i) mass flow rate, (ii) change in internal energy per kg of fluid, (iii) work done (iv) change in entropy?
12. (a) elaborate the merits and demerits of 4 stroke engines over 2 stroke engine?
(b) Derive an expression for efficiency of Ottocycle?
13. (a) Prove that the heat flow through a hollow cylinder is provided by Q = 2*3.14
(b) In a oil cooled electric transformer, 1509 kg. of oil is cooled from 80 c to 30 c in a double pipe heat exchanger using 3000 kg of water per hour available at 16 C. Assumin the overall transfer coefficient of 250 W/m2 C and flow is paralled, obtain the heat transfer area required?
14. (a) Write short note on (i) COP, (ii) Tonne f refrigeration, (iii) esential properties of refrigerants?
(b) discuss the working principle of vapour absorption refirigeration system with a line diagram/
15. (a) Name the tools and equipment used in electric arc welding?
(b) define the operation of welding?
(c) write about permanent mould casting?
(d) elaborate he important parts of a Lathe machine?
16. (a) elaborate the advantages and disadvantages of crossed belt over open belts?
(b) sketch and discuss (i) compound gear train and (ii) inverted gear train?
(c) discuss the phenomenon of slip in belts?
17. Write short notes on the following?
(a) state the 2 statemnts of 2nd legal regulations of thermodynamics.?
(b) valve timing diagram of a four stroke petrol engine?
(c) LMTD?
(d) Why fluxes are used in soldering and brazing ?
| Earning: Approval pending. |
