Effect of Wind on Thermal Performance of Heller Dry Cooling Tower

In a steam power plant, the temperature of the cooling water leaving the condenser for recycling should decrease. This is achieved in a cooling tower. The Heller cooling tower does not require water for operation, thus, it is a suitable system for use in thermal power plants throughout Iran. Wind is an environmental factor that unfavorably affects the performance of a cooling tower. Previous studies have not considered real prevailing conditions appropriately; their conclusions are incomplete and, at times, contradictory. The present field study of the cooling tower at Montazer-Ghaem Power Plant in the city of Karaj in Iran investigated the effect of wind on the thermal performance of the cooling tower. Wind velocity was measured using blade-and-cup type digital anemometers. The direction of the wind around the cooling tower was determined using tufts. Ultrasonic flow meters and resistance thermometers were used to measure the flow rates and temperatures of the water at the inlet and outlet,respectively. Results show that, despite air suction, no separation occurred at the periphery of the cooling tower. The front cooling sectors that face the wind and the back sectors that do not directly face the wind were more thermally efficient. They transferred about 60% more heat than did the cooling sectors parallel to the wind direction at the periphery of the cooling tower. The results also showed that thermal performance in the front and back cooling sectors increased as the wind velocity increased and that in the peripheral sectors decreased.

Keywords:

cooling tower , field measurements , heat transfer , power plant , wind velocity