交替边界条件下多孔床传热传质特性数值模拟  

Numerical Simulation of Heat and Mass Transfer of under Alternating Boundary Conditions

作　　者：宋潞云 张辉[1] SONG Lu-yun;ZHANG Hui(School of Energy and Environment,Southeast University)

机构地区：[1]东南大学能源与环境学院,210096

出　　处：《建筑热能通风空调》2020年第3期24-28,共5页Building Energy & Environment

摘　　要：针对回热式新风系统中多孔介质回热器在交替边界条件下的传热传质特性进行了研究。采用数值方法针对表面温、湿度交替变化的对流边界条件,对多孔床与空气的非稳态传热传质过程进行了模拟计算,获得了多孔床内温度场和含湿量场。在此基础上,分析了该类多孔床的传热传质特性,并比较了关键因素对多孔床内温度和含湿量变化的影响。计算结果表明,多孔床与空气之间的热质交换主要发生在交界面附近较浅的薄层,往底层的传递十分缓慢。多孔床与空气的热、质交换效果受气流流速影响较为明显。The heat and mass transfer characteristics of porous media regenerator under alternating boundary conditions in the regenerative fresh air system were studied. A unsteady numerical simulation calculations have been carried out to explain the heat and mass transfer characteristics in the porous bed, while the top wall of the bed is under the alternating convection boundary condition. The governing equations for the momentum, heat and moisture transfer were solved by the finite element method. Heat and mass transfer mechanisms were analyzed based on the variation of the temperature and moisture content in the porous bed.Effects of gas inlet velocity were examined under different operating conditions.The results show that the heat and mass exchange between the porous bed and the air mainly occurs in the shallow layer near the interface, and the transfer to the bottom is slow. The temperature and moisture content near the interface vary periodically because of the alternating boundary condition.The flow velocity has great influence on the heat and mass transfer between the porous bed and the air.

关 键 词：多孔介质 传热传质 数值模拟 

分 类 号：TK124[动力工程及工程热物理—工程热物理] TH43[动力工程及工程热物理—热能工程]