新型双级间接蒸发冷却系统性能理论研究

本文提出了一种新型双级间接蒸发冷却(IEC-TIEC)系统,其中普通叉流回热式间接蒸发冷却器(IEC)与热电辅助间接蒸发冷却器(TIEC)串联运行。建立了该系统的物理及数学模型,在不同热电制冷模块的运行参数(工作电流及模块数量)条件下,对比分析了新型双级间接蒸发冷却系统与单级热电辅助间接蒸发冷却(TIEC)系统的性能,结果表明IEC-TIEC系统的COP与露点效率均优于单级TIEC系统;研究了一次空气入口参数(温度、相对湿度、质量流量)对IEC-TIEC系统的COP与露点效率的影响规律。此外,对系统的四种不同质量流量分配比进行了优化分析,结果表明,存在最佳的质量流量分配比使得系统COP最大;在系统总换热面积一定的约束条件下,对系统中叉流回热式间接蒸发冷却器换热面积占系统总换热面积的比值进行了优化。

Theoretical Research on the Performance of Novel Two-stage Indirect Evaporative Cooling System

This paper proposes a novel two-stage indirect evaporative cooling(IEC-TIEC)system,in which a common cross-flow regenerative indirect evaporative cooler and a thermoelectric-assisted indirect evaporative cooler are operated in series.The physical and mathematical models of the system are established.The performances of the novel IEC-TIEC system and the single-stage thermoelectric assisted indirect evaporative cooling(TIEC)system are compared under certain operating conditions.The results show that both of the COP and dew point efficiency of the IEC-TIEC system are better than those of the single-stage TIEC system.The influences of primary air inlet parameters(temperature,relative humidity,mass flow rate)on the COP and dew point efficiency of the IEC-TIEC system are studied.In addition,four different mass flow distribution ratios of the system are optimized and analyzed.The results show that there are optimal mass flow distribution ratios resulting in maximum COP.Under the constraint of the total heat exchange area of the system,the area distribution ratio of the regenerative cross-flow indirect evaporative cooler to the total heat exchanger is optimized.It shows that there is an optimal area distribution ratio leading to a maximum COP.