Impacts of PCM Location and Thickness on Dynamic Thermal Characteristics of External Walls for Residential Buildings

The effect of PCM wall is affected by many factors. To achieve full potential of phase change material used with structural insulated panel, the present paper investigates the impacts of PCM location and thickness on dynamic thermal characteristics of external wall of residential buildings, based on numerical simulation method. First, full implicit scheme of specific heat mathematical model of phase change wall is established by using finite difference method. Then, the boundary conditions in summer and winter are obtained based on a standard residential room under free running in Xi’an through typical meteorological year data. Finally, the thermal characteristics such as internal surface temperature, decrement factor and hourly heat flux are gained for each position and certain PCM thickness under the same boundary conditions. The results show that the optimal location is the PCM layer inside of SIP external wall and the optimum thickness is 0.04 m for SIP with heat transfer coefficient of 0.45 W m⁻¹ °C⁻². The results could provide reference for engineering applications of phase change wall. The present work is a part of DeST3.0, which first introduces PCM module into DeST.