基于高分子透湿膜的全热回收器的传热传质的研究

Heat and Mass Transfer of a Total Heat Recovery with Polymer Permeable Membrane

基于高分子透湿膜的全热回收器是一种新型的高效换热器。为了更好地揭示膜换热器内部的传热传质过程,对膜全热回收器建立了空气侧、膜侧的传热传质数学模型。研究全热回收器的传热传质过程。研究结果表明,膜的热阻对显热交换的影响不大,而膜的湿阻对潜热交换有较大的影响。膜的厚度很小,湿扩散系数很大,因此膜的湿阻较小,使得新风和排风的潜热交换非常充分,结果基于透湿膜的全热回收器的潜热效率很高,达到60%以上,比基于纸的全热回收器的潜热效率高20%左右。

The polymer permeable membrane is a kind of high effective permeable materials. A parallel-struc- ture total heat recovery is fabricated and designed with PVDF membrane. The heat and mass transfer of governing equations are proposed to study the heat and mass transfer of the total heat recovery based membrane. The finite differences technique is used to discrete the partial governing equations. Numerical results indicate that the thermal resistant through the membrane side has little effect on the sensible heat exchange. However, the moisture resistant has great effect on the latent heat exchange. The thick of the membrane is small. The moisture diffusivity is great. Consequently, the moisture resistant through the membrane is small. The latent heat exchange between fresh air and exhaust air is very good. As a result, the latent heat efficient of the total heat recovery based membrane is up to 60%. Compared with the total heat recovery based paper, the latent heat effectiveness is higher than 20%.