Numerical Model of Heat and Mass Transfer for Tube-Finned Heat Exchangers under Dehumidifying Conditions

Abstract

Abstract: Dehumidifying process is very common in the evaporating conditions of finned tube heat exchangers, which has tremendous effect on the performance of heat exchangers. In order to make the simulation closer to the heat and mass transfer mechanisms, a numerical model of heat and mass transfer on air side was established. Not only is the mass transfer produced by the concentration difference between water vapor and liquid considered in this model but also the simulation of direct water vapor condensation is added by means of classical nucleation theory. The comparison between the numerical model and experimental data shows that the numerical model has good accuracy. The relative errors for jh factor and jm factor are 6.93% and 12.1% respectively. The numerical simulation shows that the relative humidity only affects the mass transfer characteristics under partial wet conditions.

Key words: dehumidifying, heat and mass transfer, numerical model

CLC Number:

TK 124

HAN Wei-Zhe, DING Guo-Liang, HU Hai-Tao, ZHUANG Da-Wei. Numerical Model of Heat and Mass Transfer for Tube-Finned Heat Exchangers under Dehumidifying Conditions [J]. Journal of Shanghai Jiaotong University, 2013, 47(03): 385-391.

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