内置格栅逆流式露点蒸发冷却器性能的数值研究
Numerical study on performance of counter flow dew point evaporative coolers with internal grille
摘要：
为提高逆流式露点蒸发冷却器的冷却效率，对冷却器进行了结构优化设计，提出了新型的内置格栅的露点蒸发冷却器。建立了描述冷却器内部热湿传递过程的二维数值模型，通过求解数值模型比较了5种结构的露点蒸发冷却器在不同入口空气温湿度、入口空气速度和二次/一次空气风量比条件下的冷却效果。模拟结果表明，内置双层格栅的露点蒸发冷却器（模型E）能有效改善干通道中一次空气分布不均匀的情况，大幅提高了冷却效率。与不含格栅的普通露点蒸发冷却器（模型A）相比，在入口空气温度(25～45 ℃)和含湿量(6.9～14.5 g/kg)条件下，模型E的湿球效率提高了10.2%～37.9%；当入口空气速度为1.5～8.5 m/s时，模型E的湿球效率平均提高了17.32%，露点效率平均提高了12.32%；当风量比为0.4～0.6时，模型E的湿球效率平均提高了20.6%，露点效率平均提高了13.6%。
Abstract：
In order to improve the cooling efficiency of the counter flow dew point evaporative cooler, optimizes the structure of the cooler and proposes a new type of dew point evaporative cooler with internal grille. Establishes a two-dimensional mathematical model describing the heat and moisture transfer process inside the cooler, and compares the cooling effect of five kinds of the dew point evaporative cooler with different inlet air temperatures and humidities, different inlet air speeds and different secondary to primary air ratios by solving the numerical model. The simulation results show that the dew point evaporative cooler with double-layer grille (model E) can effectively improve the uneven distribution of primary air in the dry channel and greatly improve the cooling efficiency. Compared with the ordinary dew point evaporative cooler (model A) without grille, the wet bulb efficiency of model E under the conditions of inlet air temperature (25 ℃ to 45 ℃) and moisture content (6.9 g/kg to 14.5 g/kg) increases by 10.2% to 37.9%. When the inlet air velocity is 1.5 m/s to 8.5 m/s, the wet bulb efficiency of model E increases by 17.32% on average, and the dew point efficiency increases by 12.32% on average. When the air volume ratio is 0.4 to 0.6, the wet bulb efficiency of model E increases by 20.6% on average, and the dew point efficiency increases by 13.6% on average.
Keywords:YangJinming,KongLinghan,DuZhenyuandJiaJie