蒸发冷却冷凝除湿复合新风系统优化

Optimization of the compound fresh air treatment system of evaporative cooling and condensing dehumidification

为降低常规热泵驱动的蒸发冷却冷凝除湿新风系统负荷,提出在常规系统流程基础上增加由表冷器和喷淋填料组成的单级全热回收模块,得到改进流程Ⅰ,并建立系统数学模型.模拟结果表明:保持系统总传热传质能力不变,系统性能随全热回收模块传热传质能力的增加先上升后下降,在典型夏季工况下,系统最优性能系数COP相比基础流程提升0.33.为减少回风全热回收过程的损失,提高送风温度,在改进流程Ⅰ的基础上增加送风显热回收模块,得到改进流程Ⅱ,此时系统性能系数COP进一步提升0.12.此外,采用多级全热回收有助于提高空气与水传热传质的匹配性,但会增加水泵功耗,对系统总体性能的提升有限.最后,搭建了基于改进流程Ⅱ的系统试验台,对上述模拟结果进行了实验验证.

In order to reduce the load of the conventional evaporative cooling and condensing dehumidification fresh air system,a single-stage total heat recovery module consisting of a cooler and a spray filler is proposed based on the basic process,and then the improved processⅠis obtained.The mathematical model of the system is established.The simulation results show that keeping total heat and mass transfer capacity of the system unchanged,the system performance first increases and then decreases with the increase of the heat and mass transfer capacity of the total heat recovery module.Under typical indoor and outdoor air conditions,the optimal COP(coefficient of performance)of the system is 0.33 higher than that of the basic process.In order to reduce the loss of exergy of heat recovery process and raise the supply air temperature,single stage of sensible heat recovery can be added to obtain the improved processⅡon the basis of the improved processⅠ,and thus the COP of the system is further increased by 0.12 compared with the improved processⅠ.In addition,multi-stage total heat recovery can improve air-water heat and mass transfer matching,but the pump power consumption is increased,so the improvement of the overall system performance is limited.Finally,an experiment table based on the improved processⅡwas built,and the simulation values were verified.