Effect of Wind on Thermal Performance of Heller Dry Cooling Tower

Abstract

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