地铁用间接蒸发冷却器换热性能影响因素

Factors affecting heat transfer performance of subway indirect evaporative cooler

为解决地铁站冷却塔设置难题,提出了一种采用低速电机驱动旋转布水装置的间接蒸发冷却器,在两种布置方式下,对其换热性能进行了单因素实验,并运用正交实验法对较优布置方式下影响换热器换热的因素进行了分析。结果表明:两种布置方式下,喷嘴与蒸发冷却器的间距、两组换热管束间距均存在最佳值,喷嘴双侧旋转布水优于单侧旋转布水;换热器平行气流布置且喷嘴双侧旋转布水为较优布置方式,此时,换热器换热量随喷水量、转速、空气速度、冷却水进口温度的增加以及喷水温度、空气温度的降低而增大,其中,冷却水进口温度对换热器换热影响最为显著,其他因素对其换热的影响从主到次顺序为:喷水量、空气温度、空气速度、喷水温度、转速、冷却水流量。

An indirect evaporative cooler installed with a rotary water distribution device which is driven by a low-speed motor, was proposed to solve the installation location problem of cooling tower in subway station. Single factor experimental method was used to investigate the heat transfer performance of indirect evaporative cooler under two types of arrangement. And under the optimal arrangement, the factors that affected the heat transfer performance were analyzed by orthogonal experimental method. The experimental results showed that the distance between nozzle and evaporative cooler and the distance between two sets of heat exchange coil under two types of arrangement both had optimal values. Rotating water on both sides was superior to rotating water on the one side. Heat exchanger arranged parallel to the air flow with nozzles rotating water on both sides was the better arrangement. And under this arrangement, heatexchange increased with the increase of spray water quantity, rotational speed, air velocity, cooling water flow rate and cooling water inlet temperature, and the decrease of spray temperature and air temperature. The cooling water inlet temperature had the most significant effect on heat transfer performance and other factors that affected the heat transfer performance from main to secondary were spray water quantity, air temperature, air velocity, spray temperature, rotational speed and cooling water flow rate.