Analysist of Unfavorable Effects of Wind on a Heller Dry Cooling Tower and Optimization of its Performance
الموضوعات : Analytical and Numerical Methods in Mechanical DesignAsadollah Ghaffari Aghababaei 1 , Ali Akbar Hosseinjani 2
1 - Department of Mechanical Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran
2 - Department of Mechanical Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran.
الکلمات المفتاحية: Heler cooling tower, wind effect, plume, wind break wall and elliptical cross section,
ملخص المقالة :
The thermal and combined-cycle power plants generally consist of several steam-electric power stations which are made and installed next to each other. Each steam-electric power station has a separate cooling tower that is responsible for heat loss of steam output from the same station. The cooling towers are built sides by sides that will be under the effect of each other during the wind blowing of the surrounding environment. Some studies works have shown the unfavorable effects of wind arises two factors of the vortex flow around the radiators and tilting the exhaust plume of their flues. They purposed in order to reduce these effects use windbreak wall next to the radiators or tilting the exhaust plume. This study use both purposes simultaneously, considering a tilting the exhaust plume with elliptical cross section, a dry cooling tower is simulated. The results are compared with the obtained results whit a simple cooling tower with circular section in two cases; no wind conditions and a wind of 3 m/s speed. This comparison shows that the cooling tower with elliptical cross exposing front of wind has better performance. A more examination of the results it reveals that the cooling tower with elliptical cross section with a diameter ratio of 2:1 is determined a optimum cross section which in compared of circular cross section has 12% higher efficiency.
[1] Kapas, “Behavior of Natural Draught Cooling Towers in Wind”, CMFF, 30, Budapest, Hungary, 2003.
[2] A.F.DuPreez, and D.G. Kroger, “Effect of Wind on Performance of a Dry- Cooling Tower”, Heat Recovery Systems and CHD, VOL. 13, pp. 139-146, 1993.
[3] Wei Q., Zhang B., Liu K., Du X., and Meng X., “A Study of The Unfavorable Effects of Wind on the Cooling Efficiency of Dry Cooling Towers”, Journal of Wind Engineering and Industrial Aerodynamics, Vols. 54 and 55, pp. 633–643, 1995.
[4] Al-Waked R., Behnia M., “The Performance of Natural Draft Dry Cooling Towers under Cross Wind: CFD Study”, International journal of energy research, Vol. 28, pp. 147-161, 2004.
[5] Parvizi. Bahram, "Analysis and investigation of the negative impact of wind on the performance of dry cooling towers in power plants and providing a solution," Master's thesis, Mechanical Engineering, Energy Conversion, Tarbiat Modares University, 2007.
[6] B. Gebhart, “Buoyancy-Induced Flows and Transport”, Textbook Edition, Hemisphere Publishing Corporation, 1988.
[7] B. E. Launder, and D. B. Spalding, “The Numerical Computation of Turbulent Flow”, Comput. Metods Appl. Mech. Eng, Vol. 3, pp. 269-289, 1974.
[8] “The Heller System”, EGI, Budapest, 1984.
[9] Dr. Goodarzi. Mohsen, Raofi. Mina, "A design proposal for the shape of the dry cooling tower chimney in order to reduce the adverse effects of wind," Proceedings of the First National Conference on Power Plants, pp. 206-213, Qazvin, Imam Khomeini International University, March 2008.
