用于液体除湿的椭圆中空纤维膜管束管间传递现象

摘要

Axial momentum and heat transfer between an elliptical hollow fiber membrane tube bank (EHFMTB) used for liquid desiccant air dehumidification are studied. Two regular arrangements, in-line and staggered, are considered. Two unit cells consisting of two fibers and the fluid flowing longitudinally between the fibers are selected as the calculation domains. The governing equations for the fluid flow and heat transfer between the EHFMTB are established and solved via a boundary-fitted coordinate transformation method. The friction factor and the Nusselt number in the unit cells are obtained. The variation of local Nusselt number along the tube length is analyzed. The effects of pitch-to-diameters, elliptical semiaxis ratios and wall surface conditions on these data are investigated. The results are useful for performance evaluations of the EHFMTB.%研究了用于液体除湿的椭圆中空纤维膜管束管间纵向动量与热量传递现象。选择了四边形和三角形排列这两种规则排列管束中的两根纤维管和管间流体为研究对象，建立控制管间纵向流体流动与传热过程的偏微分方程，并采用贴体坐标转换法对控制方程进行有限容积离散与求解，获得了计算单元内的阻力系数和Nusselt数，分析了流道内局部Nusselt数的变化特征以及纤维管排布（三角形和四边形排列）、管径比、椭圆半轴比以及壁面边界条件（等壁温或等热通量边界）的影响。研究结果可为用于液体除湿的椭圆中空纤维膜管束的结构设计和性能评价提供基本理论及数据基础。