NUMERICAL SIMULATION OF FLOW FIELDS IN A NATURAL DRAFT WET-COOLING TOWER

The flow field in the hyperbolic natural draft wet-cooling tower, which has great effects on the economy and security of power plant, was studied through numerical simulation. The mathematical model was established and analyzed in order to optimize the cooling-tower and to evaluate its efficiency. Various working conditions were considered and compared with each other, such as the circulating water flux, air temperature and tower resistance. It is concluded that when the cooling-tower runs without wind, there is a vacuum region inside the tower and the pressure rises with the increase of the tower height. Meanwhile, the inner flow field is axisymmetrical. The air velocity achieves its climax at the axis. It is also found that the effect of circulating water temperature is equivalent to that of the water flux.

间接空冷散热器防冻问题的数值模拟分析

利用计算流体力学软件Fluent对康巴什热电厂350 MW机组间接空冷塔内布置的表面式空冷散热器空气侧和水侧的流动特性及换热性能进行数值模拟,以获取间接空冷散热器中的低温区。结果表明:无论风向如何变化,迎风侧的扇区与其他扇区相比,温度最低。而在同一扇区内,供水支管附近的矩形冷却器第20—24号小管内温度最低,为间接空冷机组冬季扇区投退、重点部位温度监测提供理论支持。