板式间接蒸发冷却器传热传质系数的研究  

Study on Heat and Mass Transfer Coefficient of Indirect Evaporative Cooling in Plate Heat Exchanger

作　　者：丁杰[1] 任承钦[2] 

机构地区：[1]株洲南车时代电气股份有限公司 [2]湖南大学机械与汽车工程学院

出　　处：《建筑热能通风空调》2007年第5期1-6,10,共7页Building Energy & Environment

摘　　要：间接蒸发冷却器内涉及同时发生的传热与传质过程,传热传质机理非常复杂。本文在数值模拟基础上分析了温度场与浓度场、局部Nu数与局部Sh数的分布特点以及不同因素对平均Nu数和平均Sh数的影响。应用一个无量纲数θ以考虑二次空气干、湿球温度和一次空气干球温度对对流传热传质的影响。拟合得到了平均Nu数与平均Sh数关于Re数和无量纲数θ的计算式。该结果为板式间接蒸发冷却器的设计提供了理论指导。Since heat and mass transfer occur simultaneously in an indirect evaporative cooler, the mechanisms of heat and mass transfer process is more complex compared with that in a sensible heat exchanger. The characteristics of the distributions of the temperature, the concentration, the local Nusselt number and the local Sherwood number were discussed based on numerical simulation. The effects of variable parameters on mean Nusselt and Sherwood numbers were also investigated. Correlations for average Nusselt and Sherwood numbers were developed in terms of Reynolds numbers and a new dimensionless parameter θ, which takes into account the effects of the inlet dry-bulb and wet-bulb temperatures of the secondary air stream and the inlet dry-bulb temperature of the primary air stream. The results are useful for the design of an indirect evaporative cooler.

关 键 词：间接蒸发冷却 传热传质 Nu数 Sh数 

分 类 号：TU831.6[建筑科学—供热、供燃气、通风及空调工程]