Performance trends of an air-cooled steam condenser under windy conditions

Air-cooled steam condensers (ACSCs) are increasingly employed to reject heat in modem power plants. Unfortunately, these cooling systems become less effective under windy conditions and when ambient temperatures are high. A better understanding of the fundamental air flow patterns about and through such ACSCs is essential if their performance is to be improved under these conditions. The present numerical study models the air flow field about and through a particular ACSC The performance of the fans is modeled with the aid of a novel numerical approach known as the "actuator disc model." Distorted airflow patterns that significantly reduce fan performance in certain areas and recirculatory flows that entrain hot plume air are found to be the reasons for poor ACSC performance. It is found that the reduction in fan performance is the main reason for the poor ACSC performance while recirculation of hot plume air only reduces performance by a small amount.