运行状态下超大型冷却塔内表面风荷载的数值模拟研究

对运行状态下的某超大型双曲冷却塔的内表面平均风压进行了CFD数值模拟.在计算流体动力学软件基础上进行二次开发，采用DPM模型结合UDF函数方法加入源项来研究某超大型冷却塔内表面平均风压分布；塔中水相采用了拉格朗日方法模拟，而空气相采用欧拉方法模拟，较好地实现了冷却塔运行状态下的内外流场计算及其与传热传质的耦合计算，分析了运行状态下冷却塔横风向来流时的内压分布规律.无侧风工况下计算结果显示，塔运行过程中的内表面压力对称性良好，出水温度与实测结果相符，验证了本文提出的塔运行过程中的传热传质计算方法的正确性.侧风工况下得到塔内压力系数沿高度方向相应变大，而沿纬向变化不明显.同时讨论了中国规范对内表面压力系数的取值不完善之处，给出了建议取值，为超大型冷却塔设计过程中的内压计算提供方法和依据.
The average wind pressure on the internal surface of a super large hyperbolic cooling tower under the operating conditions was simulated in CFD method. Based on computational fluid dynamics software for secondary development, DPM model combined with a UDF function method was used to study the average wind pressure on the internal surface of a super large cooling tower. The Lagrangian method was used to simulate the water phase of the tower and Euler method was adopted to simulate the air phase, the coupling calculation between inner flow field and transformation of heat and mass in cooling tower under the operating conditions was well realized, and the internal pressure distribution law of cooling tower under crosswind direction with running state was analyzed. The results of the tower with no cross wind show that the symmetry of the average pressure on the internal surface goes well, and the water temperature is consistent with the test result, which verifies the effectiveness of the method proposed. The value of the average pressure coefficient of the internal surface of cooling tower under cross wind becomes bigger along the height direction, and the value does not change significantly along the latitudinal direction. The shortcomings of the current code about internal surface pressure coefficient were discussed, and the recommended values were given, which provides methods and basis for the calculation of the internal pressure of super large cooling tower design.