Flow deflectors to release the negative defect of natural wind on large scale dry cooling tower

In order to reduce the unfavorable impacts of natural wind, the arc curved air flow deflectors were proposed to be settled around the natural draft dry cooling tower. Based on 2 x 600 MW indirect air cooling power generating units, the thermo-fluid models of the natural draft dry cooling tower coupled with condenser of turbine are developed, by which the cooling performances are investigated at natural wind speed ranged from 0 to 20 m/s. The numerical results with experimental validations illustrate the thermo-fluid performance distributions of different cooling sectors around the dry cooling tower. It can be obtained that in the presence of ambient natural wind, the proposed deflectors could extend the positive effects of natural wind, leading to the decrease of outlet temperature of circulating water and back pressure of turbine. Compared to the case without deflectors, the total air mass flow rate could be increases by 50.26%, the outlet temperature of circulating water could be decreased by 10.73 degrees C and the back pressure of turbine could be decreases by 7.33 kPa when the wind speed is 20 m/s. In the absence of wind, the changes of air mass flow rate, heat rejection, outlet water temperature and back pressure are all no more than 0.5% compared with that without the deflectors, implying almost no negative impacts of the proposed deflectors under various operating conditions. The natural wind direction has little influence on the performance of natural draft dry cooling tower with deflectors. (C) 2018 Elsevier Ltd. All rights reserved.