ENERGY AND EXERGY ANALYSIS OF COUNTER FLOW WET COOLING TOWERS

Abstract

Cooling tower is an open system direct contact heat exchanger, where it cools water by both convection and evaporation. In this paper, a mathematical model based on heat and mass transfer principle is developed to find the outlet condition of water and air. The model is solved using iterative method. Energy and exergy analysis infers that inlet air wet bulb temperature is found to be the most important parameter than inlet water temperature and also variation in dead state properties does not affect the performance of wet cooling tower.

Keywords

Dates

  • Submission Date2007-04-05
  • Revision Date2008-02-27
  • Acceptance Date2008-03-09

DOI Reference

10.2298/TSCI0802069S

References

  1. Merkel, F., Evaporative Cooling, VDI-Zeitchrift, 70 (1925), 70, pp. 123-128
  2. Threlkeld, J. L.,Thermal Environmental Engineering, Prentice-Hall Inc., Englewood Cliffs, N. J., USA, 1970
  3. Sutherland, J. W., Analysis of Mechanical-Draught Counter-Flow Air/Water Cooling Towers, ASME Transaction, 105 (1983), 3, pp. 576-583
  4. Zubair, S. M., Khan, J. R., Yaqub, M., Performance Characteristics of Counter Flow Wet Cooling Towers, Energy Conversion and Management, 44 (2003), 13, pp. 2073-2091
  5. Kloppers, J. C., Kroger, D. G., The Lewis Factor and its Influence on the Performance Prediction of Wet-Cooling Towers, International Journal of Thermal Sciences, 44 (2005), 9, pp. 879-884
  6. Cengel, Y. A., Wood, B., Dincer, I., Is Bigger Thermodynamically Better? Exergy, an International Journal, 2 (2002), 2, pp. 62-68
  7. Rosen, M. A., I. Dincer Effect of Varying Dead-State Properties on Energy and Exergy Analyses of Thermal Systems, International Journal of Thermal Sciences, 43 (2004), 2, pp. 121-133
  8. Smrekar, J., Oman, J., Sirok, B., Improving the Efficiency of Natural Draft Cooling Towers, Energy Conversion and Management, 47 (2006), 9-10, pp. 1086-1100
  9. Bejan, A., Advanced Engineering Thermodynamics, 2nd ed., John Wiley & Sons, New York, USA, 1997
  10. Moran, M. J., Availability Analysis: A Guide to Efficient Energy Use, ASME Press, New York, USA, 1989
  11. Bejan, A., Tsatsaronis, G., Moran, M. J., Thermal Design and Optimization, John Wiley & Sons, New York, USA, 1996
  12. Tsatsaronis, G., Definitions and Nomenclature in Eexrgy Analysis and Exergoeconomics, Energy, 32 (2007), 3, pp. 249-253
  13. Chengqin, R., Nianping, L., Guangfa, T., Principles of Exergy Analysis in HVAC and Evaluation of Evaporative Cooling Schemes, Building and Environment, 37 (2002), 11, pp. 1045-1055
  14. Qureshi, B. A., Zubair, S. M., Second-Law-Based Performance Evaluation of Cooling Towers and Evaporative Heat Exchangers, International Journal of Thermal Sciences, 46 (2007), 2, pp. 188-198
  15. Thirapong, M., Wanchai A., Somchai, W., An Exergy Analysis on the Performance of a Counterflow Wet Cooling Tower, Applied Thermal Engineering, 27 (2007), 5-6, pp. 910-917
  16. ***, ASHRAE Equipment Guide, American Society of Heating, Refrigerating, and Air Conditioning Engineers, Inc; Atlanta, Geo., USA, 1983, Chapter 3
  17. ***, ASHRAE Handbook of Fundamentals, American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc, Atlanta, Geo., USA, 2001, Chapter 6
  18. Simpson, W. M., Sherwood, T. K., Performance of Small Mechanical Draft Cooling Towers, Refrigerating Engineering, 52 (1946), 6, pp. 525-543, 574-576
  19. Wark, K., Advanced Thermodynamics for Engineers, McGraw-Hill, New York, USA, 1995
Volume 12, Issue 2, Pages69 -78