鼓风式机械通风冷却塔空气动力特性数值模拟研究

Numerical simulation research on aerodynamic characteristics of the forced draft mechanical cooling tower

鼓风式机械通风冷却塔常用于核电厂的重要厂用水系统,但目前的相关设计规范并没有给出冷却塔的空气动力特性计算公式。该文采用Fluent软件对鼓风式机械通风冷却塔的空气动力进行了数值模拟计算,对冷却塔的设计布置进行了优化,分析总结给出了冷却塔阻力计算公式。结果表明:填料安装高度对鼓风式机械通风冷却塔整塔阻力影响不大,但会影响填料断面风速分布均匀性,填料安装高度越低,风速分布越均匀;出口收缩段的高度越高,整塔阻力越小,风速分布越均匀;出口收缩段与水平的夹角越大,整塔阻力系数越小,但变化趋势不明显,收缩角基本不影响填料断面风速分布均匀性。

The forced draft mechanical cooling tower is always used in a nuclear power plant, while the relevant design specification have not formulas about the aerodynamic characteristics of the forced draft mechanical cooling tower. With FLUENT software, this paper establishes a numerical model to simulate and study the aerodynamic characteristics of the forced draft mechanical cooling tower, and optimize the design of the cooling tower, and summarize the formula about cooling tower resistance. The results show that the height of the fill has little effect on the whole tower resistance coefficient, but it influences the wind velocity distribution uniformity on the fill section, the lower the position is, the more uniform the wind velocity distribution is; the convergent section height is higher, the whole tower resistance is smaller and the wind velocity distribution is more uniform; the angle between convergent section and horizon is bigger, the whole tower resistance is smaller, while this trend is not obvious, this angle does not affect the wind velocity distribution uniformity on the fill section.