Paper Conference

Proceedings of eSim 2008: 5th Conference of IBPSA-Canada

     

FINITE ELEMENT MODELING FOR SOLID-SOLID PHASE CHANGE MATERIALS WITH VARYING HEATING AND COOLING PHASE CHANGE TEMPERATURES

Dahai Zhang, Alan Fung, Omar Siddiqui

Abstract: Phase change materials (PCMs) can be implemented into building practice to enhance thermal storage performance, reduce indoor temperature fluctuations and improve the comfort of occupants. Solid-solid PCMs (SSPCMs) have unique properties which make them superior to the traditional solid-liquid PCMs (SLPCMs). These include an enhanced structural integrity and ease of incorporation with building fabrics. In order to investigate any new type of SSPCM, it is desirable to have a finite element model (FEM) for the thermal performance validated by the experimental data. Due to the impurity and thermal instability, practical PCMs usually do not have the same phase change temperatures on heating and cooling processes. This varying thermal property will affect the validation of FEM, if it is not properly represented. In current study, a mathematical model for SSPCMs will be described and a corresponding FEM will be created in FEMLAB. A script was written for the FEMLAB solver to alter the phase change temperature automatically based on the heating and cooling mode. The enthalpy method and effective heat capacity method were used for the simulation.
Pages: 94 - 98
Paper:
esim2008_094_098