Guess Questions for Sessional October, 2014

Objective types

A. What do you mean by microscopic and macroscopic approach of thermodynamic study?B. Define BUE.C. Define drilling, boring and reaming.D. What do you mean by thermometric property?E. What is psychrometry and psychrometric charts?F. What is the difference between coefficient of performance and thermal efficiency?G. What is the difference between heat pump and refrigerator?H. What do you mean by quality of steam, how does it get defined?I. Define triple point and critical point of water?J. Define dew point temperature (DPT), wet bulb temperature (WBT) and dry bulb temperature (DBT).K. What do you mean by point function and path function?L. Describe oblique cutting.M. What is the chemical formula for R-143, R-134a, R-717 and R-744?N. What is human comfort?O. Derive the COP for refrigeration system?P. Define third law of thermodynamics?Q. What do you mean by priming, how does it get defined?R. Define saturation curve of water?S. Why reversible Carnot engine is not feasible in reality?

Subjective

1. What are the four thermodynamic laws? Explain in brief with their limitations and applications.2. Explain milling machine with neat sketch and operations performed in brief.3. Derive expression for reversible isothermal and reversible adiabatic closed system work done.4. What is the second law of thermodynamic? Derive work done and heat interaction for an adiabatic

process.5. Explain shaping machine with neat sketch and operations performed in brief.6. What are the types of chips formed during machining process and describe them briefly? 7. Difference between orthogonal and oblique cutting?8. What are the types of chips formed during machining process and describe them briefly?9. Difference between up-milling and down-milling?10. Describe simple vapour compression cycle with neat sketch including every process.11. Differentiate between fire tube boilers and water tube boilers.12. Explain accessories, economizer and mounting, with one working for each process.13. Explain the working of air-preheater with neat sketch.14. Explain working of throttling calorimeter with diagram.15. What do you mean by sensible heat, latent heat, sub cooled region and superheated region?16. Derive an expression for entropy change in reversible isothermal and adiabatic process.17. Describe a window air conditioning simple vapour compression cycle with neat sketch including

every process. 18. Explain barrel calorimeter.

Numerical

1. A Freon 12 vapour compression system operates between a condenser temperature of 313K and evaporator temperature of 273K, develops 15TR. Enthalpy of vapor refrigerant entering compressor is 187.5 KJ/Kg, after compressor enthalpy is 213.96KJ/Kg. enthalpy of liquid refrigerant is 74.6KJ/Kg. Find out mass flow rate of refrigerant, refrigeration effect, power consumption, heat rejected, Carnot COP and COP of the cycle.

2. An ideal gas is heated at constant volume until its temperature is three times the original temperature. It is then expanded isothermally until it reaches initial pressure. Gas is then cooled at constant

pressure till it restore to the initial state. Find the net work done by the gas per Kg. Initial temperature is 350K, gas constant for it is 0.287Kj/Kg-K and ideal gas equation for per Kg is PV=RT.

3. A heat engine working on a Carnot cycle draws heat from two different high temperature reservoir and rejects heat to a low temperature reservoir at 300K at the rate of 200KJ/s, produces work of 4KW. If the temperature of high temperature reservoirs are 800K and 500K, find out heat transferred from the reservoirs