Theoretical Analysis And Experimental Research On The Heat And Moisture Transfer Of Phase Change Porous Building Envelope Materials

This paper?which is on the basis of analyzing the theory of heat and moisturecoupling transfer on porous materials?both in China and abroad?linking with theresearch requirement for the heat and moisture model of the building envelope?learning from the existing heat and moisture coupling transfer model?specific to theapplication of phase change energy storage material in the building wall?consideringthe absorption and desorption of the porous wall as well as the exothermic orendothermic of the phase change materials?established the model for evaluatingcoupled heat and moisture transfer in porous wall with phase change materials. andthe parameters in the model were tested and analyzed.At first? gypsum was chose as the porous matrix materials.The thermalparameters of the matrix material and the gypsum with phase change material weretested by the Differential Scanning Calorimetry (DSC).And analyzing and fitting thethermal performance variation of the gypsum with different PCMproportion.According to analysis and compare the variation of the phase change latentheat?advanced the phase change criterion which is the significant thermal performanceparameter.The second?the moisture parameters of the gypsum matrix and gypsum withPCM?which include convective moisture transfer coefficient?moisture diffusioncoefficient?thermogradient coefficient?were tested by the use of saturated salt solutionand the "cup" test method,while providing the basis for solving the model.The last?according to the established mathematical model and the heat and moisture parametes?the differential equations were solved by the use of COMSOLsoftware.And then the temperature and moisture distribution curves of the buildingwall were given. Through the temperature and moisture experimental simulation?theresults show that the theoretical analysis model and the measured results have a goodagreement?so verified the theoretical analysis model has a certain practicality.