Numerical Simulation Of Air Flow And Heat Transfer Characteristics In Air-Cooled Condenser

It is of great interest to study the influences of ambient conditions on the flow and heat transfer of cooling air in direct air-cooled system for improving the operation performance of air-cooled system in power plant.Firstly,based on the typical structure of the air-cooled condenser of 600 MW unit,the physical and mathematical models of an air-cooled condenser cell with external & internal flow guiding device were established. The velocity and temperature fields of the cooling air in the condenser cell were obtained by CFD simulation.The influence of the flow guiding device upon the flow and heat transfer of the cooling air was analyzed at different ambient conditions.Secondly,based on 2×300MW direct air-cooled units,the operation performance of the direct air-cooled system at different wind directions were analyzed.The results show that external flow guiding device can effectively reduce the adverse effects of the ambient cross wind, increase the flow rate of the cooling air and improve the heat transfer of the condenser cell;internal flow guiding device can enhance the flow field uniformity of cooling air and reduce the temperature of the cooling air.Different wind directions lead to different disadvantageous regions of heat transfer of air in direct air-cooled system.The higher the speed of the wind,the larger the effect on operation performance of direct air-cooled system.