The optimal allocation of the PCM within a composite wall for surface temperature and heat flux reduction: An experimental Approach

Abstract

In the objective to enhance the thermal inertia of the light envelopes based on the lightweight materials such as the wood, the integration of the phase change materials in these envelopes is suggested. However, the critical design challenge is the allocation of the PCM within building walls. In this work, a reduced scale cavity has been built and monitored. Its thermal performance is evaluated in four possible PCM allocations. The cavities at reduced scale provide the flexibility to test most kinds of wall constructions in real time and allows for the faster installation and dismantling of the test walls. The use of the cavity at reduced scale concept is demonstrated by evaluating the thermal performance of a thin phase change material (PCM) layer and its allocation inside the wall. The optimal allocation is studied based on the wall surface heat flux and surface temperature reduction. The results show that, first of all, the location of PCM layer close to the heat source reduces the surface temperature by 2°C and no effect is observed when the PCM layer is placed far from the heat source. Indeed, the allocation PCM/Wood/PCM/Wood was be selected to be the optimal allocation for its great impact on the surface temperature and heat flux. In this configuration, the maximum surface temperature and peak heat flux are 19,502°C and 37.093W/m2.