The Effect of Wind Screens on the Performance of an Induced Draft AirCooled Condenser Under Windless and Windy Conditions

Abstract

Wind generally reduces the thermal effectiveness of aircooled condensers (ACCs). Therefore, this study investigates wind screens as a means to improve the performance of a 20fan induced draft ACC under windy conditions. Two windscreen configurations are tested: walls extending above the fan platform (termed wind walls) and walls extending below the fan platform (termed wind skirts). The performance of this fivebyfour ACC is evaluated using the opensource computational fluid dynamics code, OpenFOAM. The performance is first analyzed under windless operating conditions and then when the ACC is subjected to wind speeds of 3, 6, and 9 m/s directed along the shorter and longer axes of the ACC. Under windless conditions, wind walls increase the ACC’s thermal effectiveness by 1.0%. Wind skirts, however, reduce the effectiveness by 1.8%. Depending on the wind speed and direction, wind walls increase the mean thermal effectiveness of the ACC by 0.3–3.9% under windy conditions. Wind skirts, on the other hand, are only beneficial at higher wind speeds: At 3 m/s, the effectiveness declines by 1.4–2.1%; at 6 m/s, the change in effectiveness ranges from −0.4% to 2.2%; and at 9 m/s, the effectiveness increases by 2.4–3.8%. Wind walls are therefore considered more effective than wind skirts for the tested range of wind speeds.