The Numerical Simulation Of The External Flow Field And Structure Optimization For Air-cooled Island Of Direct Air-cooled Unite Units

Direct air-cooled condenser expose to the air, heat exchange with the surrounding air to achieve the listing of role of the condensate, so the environmental wind is bound to have effect on the normal operation of the air-cooled condensers.The numerical simulation of the external flow filed of the air-cooled island was made with CFD for a 600MW direct air-cooled unit.The effect of the different wind speed on the heat transfer efficiency of direct air-cooled condensers was analyzed, the results shows, when the wind speed exceeded 7m/s, that the main reason of the heat-transfer efficiency fall in the air-cooled condenser is due to the combined action of the hot air recirculation and its downdraught. In the paper, the effect of the lower windbreak of different shapes located in different position in air cooling island on the heat transfer efficiency was further analyzed, The research results provide some theory evidence for the structural design and optimization of the air-cooled island.