冷却塔混凝土粗糙度对平均风压系数的影响

采用CFD方法研究全尺寸双曲冷却塔表面混凝土粗糙度对风压系数的影响.在规范规定的粗糙度范围内，分别对表面混凝土光滑以及表面混凝土有不同粗糙度高度的冷却塔全尺寸模型进行了数值模拟.将不同工况下的风压系数计算值与以往文献的风洞试验和现场实测数据进行了比较.研究结果表明：冷却塔全尺寸CFD模拟虽然解决了雷诺数相似问题，但纯粹的光滑壁面冷却塔在CFD计算中得到的平均风压系数比实际值偏离较大；在冷却塔全尺寸CFD模拟中必须考虑实际冷却塔表面的粗糙度对其平均风压系数的影响.

Effect of Surface Roughness on the Mean Pressure Coefficient of Concrete Cooling Tower

CFD technique was employed to investigate the effect of surface roughness on the mean pressure coefficients of a full-scale cooling tower. Six kinds of surface roughness with smooth surface and varying roughness heights, as covered by the design code, were studied for a full-scale cooling tower. The numerical results were compared with the wind tunnel and full-scale measurement results from published works. It has been shown that, when full-scale-based CFD simulation successfully circumvents the Reynolds similitude, the smooth tower section has a large mean wind pressure coefficient than the rougher tower sections. It is therefore concluded that the real surface roughness must be reproduced in the evaluation of the mean wind pressure coefficient of cooling towers.