新型鼓风式机械通风冷却塔进风口阻力优化

Inlet resistance optimization of a new type of mechanical ventilation cooling tower

鼓风式机械通风冷却塔常应用于核电厂重要厂用水系统,为了提高其安全性,提出了一种新型鼓风式冷却塔,但由于结构复杂,其阻力特性不同于常规的鼓风式机械通风冷却塔。针对新型鼓风式机械通风冷却塔的阻力问题,通过三维模型研究了塔内阻力构成,进而确定进风口的优化方案。结果表明,初始方案冷却塔的各部分阻力中,从进风口防飞射物的过滤网至风机外罩入口的阻力最大(约占32.7%)。优化方案在满足防飞射物入侵的前提下,通过调节进风口相关尺寸,使塔入口至网面的阻力系数占比降低了4.8%,网面至风机入口的阻力系数占比降低了1.8%。

A blast-type mechanical ventilation cooling tower is often used in important plant water system of nuclear power plant.In order to improve its safety,a new type of air-blast cooling tower is proposed.However,because of its complex structure,its resistance characteristics are different from those of a common mechanical ventilation cooling tower.The resistance problem of a new type of mechanical ventilation cooling tower was studied by using a three-dimensional model,and the composition of the resistance in the tower was analyzed,so as to determine the optimal scheme of the air inlet.The results show that in the initial cooling tower,the resistance from the filter to the fan inlet is the largest(about 36%).In the optimization model,the percentage of the resistance coefficient from the tower inlet to the filter is reduced by 4.8%and that from the filter to the fan inlet is reduced by 1.8%by adjusting the area of the cross section of the inlet under the premise of preventing the invasion of flying object.