自然通风逆流式冷却塔外区配水一维热力计算方法

ONE-DIMENSIONAL CALCULATION METHOD OF THERMAL PERFORMANCE FOR NATURAL DRAFT COUNTER FLOW COOLING TOWER WITH WATER DISTRIBUTION IN THE OUTER AREA

在我国的北方地区,自然通风逆流式冷却塔冬季或春秋季一般采用外区配水的运行方式,塔内的一部分区域不淋水,而此时传统的热力计算方法将不再适用。通过对塔内的热空气密度进行了线性关系及雨滴阻力均匀的简化假设后,推导出了冷却塔外区配水的一维热力计算方法。经与原型实测数据的对比,计算误差不大于0.3℃,吻合良好,可供设计参考。

In winter, spring,and autum seasons at norther area in China, the natural draft counter flow cooling towers were generally adopting an operation mode with water tricking in the outer area of the cooling tower,while in a part of the centre area,there isn＇t water tricking. In this case,however,the traditional calculation method of thermal performance will be unsuitable to use. Through simplified assumption that the density of hot air is changing linearly with the height of tower, and the resistance of rain droplets is even with the their radiuses,an one- dimensional calculation method for thermal performance of cooling towers with water destribution in the outer area has been deduced and obtained. After comparison with the prototype measured data,the calculation error isn＇t greater than 3℃ ,tallying well with the measured data, providing reference for the cooling tower design.