除湿换热器串联换热器强化除湿降温性能实验研究

除湿换热器可以同时处理显热与潜热负荷,但由于吸附热的影响,存在热湿负荷处理不同步及显热负荷处理能力不足的问题。本文提出了在除湿换热器后面串联一个显热换热器对空气进行二次处理,搭建了实验台对除湿换热器串联换热器情况下除湿降温过程的动态性能进行测试,并且在实验中分析了水温、进风温度、湿度、速度等主要参数对除湿量、降温量、制冷功率、COP的影响。结果表明:增加显热换热器可以大幅度增加处理空气的平均降温温差,在除湿初期阶段效果尤为明显,同时系统的制冷量也明显提高。此外,分析各参数对实验结果的影响可知,冷水温度与热水温度升高都可以有效提高系统制冷量与COP,空气的温湿度升高会提升系统性能,空气流速变慢对系统平均除湿量与有效除湿时间有明显的提升。

Experimental Investigation on Thermal Performance of Desiccant Coated Heat Exchanger in Series with Heat Exchanger

A desiccant coated heat exchanger can handle sensible load and latent load simultaneously; however, owing to the influence of adsorption heat, the heat load and moisture load treatment is not synchronous, and the ability to handle sensible load is insufficient. Based on this, another sensible heat exchanger is added in-series for the air secondary treatment. An experiment setup was built to test the dynamic performance of two heat exchangers connected in-series. In addition, the influence of the main operation parameters including the water temperature, air temperature, air humidity, and air velocity on the system performance are analyzed. The results show that a sensible heat exchanger can clearly improve the ability to handle sensible load, particularly during the beginning period, and the cooling capacity of the system is also significantly improved. Moreover, under the experiment conditions, the cooling and heating water temperatures can both improve the cooling capacity and COP, a higher air temperature and relative humidity ratio lead to a better performance, and a lower air velocity is helpful for increasing the average dehumidification capacity and the effective dehumidification time.