建筑墙体热质传递等效耦合扩散模型建立

Establishment of equivalent coupled diffusion model for the transfer of heat and mass in the building walls

针对建筑墙体的热传递、湿传递及空气渗透的3个过程,根据多孔介质中多相流体流动描述的体积平均方程,建立了热、湿和空气耦合作用下的墙体热质传递模型,推导了热、湿和空气耦合传递等效扩散方程,分析了建筑墙体热、湿及空气耦合作用下热质传递过程的主要影响因素———湿容量θL、气压pG和温度T.

Heat transfusion, moisture transfusion and air permeability occur in building walls. According to the volume balance equation of the description of the multiphase fluid flow in the porous media, we have established the wall heat transfer model under the coupled effect of heat, moisture and air and derived equivalent coupled diffusion equation of the coupled transfer of heat, moisture and air. The general mass balance equation can be expressed by the temporal change of moisture contentθL, gas pressure PG and temperature T which are the most dominant influencing factors in the coupled heat and mass transfer process.