A novel method integrating windbreak walls with water distribution to mitigate the crosswind effects on natural draft dry cooling towers

Abstract

This paper proposed a novel method combining both air side optimization (windbreak walls) and water side optimization (water distribution) to reverse the side effects of crosswind on natural draft dry cooling towers (NDDCTs). A three dimensional (3-D) numerical model of a 20 ​m NDDCT based on the University of Queensland NDDCT Gatton test rig is developed. Windbreak walls, designed at three different attack angles towards wind direction (α ​= ​0°, 30° and 60°), could generate an extra amount of the cooling capacity especially at high crosswind speeds, but the contribution is sensitive to the wind attack angles. While water distribution to improve the cooling performance of Gatton NDDCT is not as good as that brought by windbreak walls. However, water distribution could make use of the non-uniform air flow distribution caused by windbreak walls, exploring much more cooling capacity under windy conditions, therefore. With the favor of water distribution, the cooling performance of Gatton NDDCT with walls could be further lifted by 1.37%, 3.24%, 5.75%, 9.66%, 13.07% and 16.06%, respectively from vcw ​= ​3 ​m/s to 8 ​m/s. In summary, the cooling performance of Gatton NDDCT can be lifted beyond or almost maintained at the designed value under all crosswind speeds and wind attack angles.