Experimental and Numerical Thermal Properties Investigation of Cement-Based Materials Modified with PCM for Building Construction Use

Due to their latent heat storage capacity, phase-change materials (PCM) incorporated in wallboards are an effective solution to reduce energy consumption inside buildings. This is achieved by incorporating PCM in construction elements made of cement-based materials. The purpose of this research is to evaluate both the thermal conductivity and the heat storage capacity of mortars and concretes with different amounts of PCM in order to evaluate their thermal performance. Therefore, a laboratory-developed transient plane source experimental setup was used to measure these properties. First, several mortar and concrete specimens including different amounts of PCM (0%, 4.5%, 9%, and 13% by total mass of cement) were manufactured. Then, the experimental setup was used to measure the temperature development on PCM-concretes and PCM-mortars for a period of 1,000 s. The collected data were analyzed to back-calculate the thermal characteristics using a numerical optimization procedure. Numerical findings using the finite-element method show that the testing procedure efficiently provides accurate estimations of the thermal properties of the tested specimens. It was found that cement-based materials incorporating PCM have lower thermal conductivity and higher heat storage capacity, which indicates the improvement of their thermal behavior

Experimental and numerical analysis of the energy efficiency of PCM concrete wallboards under different thermal scenarios

This paper aims to investigate the energy efficiency of PCM-concrete wallboards using experimental and numerical approaches. First, a laboratory experimental work was performed to manufacture PCM-concrete mixtures with different proportions of PCMs. Then, an innovative bench test based on the transient plane source theory was used for the thermal analysis of the mixtures. Besides, numerical simulation by finite element method was carried and the confrontation of the numerical results with the experience has showed an excellent agreement. Accordingly, the numerical approach was validated and generalized for the study of PCM-concrete at macro scale under different thermal scenarios and PCM distributions (homogeneous/Bilayer/Matrix-inclusions). The numerical simulations highlighted clearly the role of PCMs in decreasing the indoor temperature of the different PCM-wallboards as well as the thermal fluctuations. Moreover, the time delay in the temperature peaks emphasized the enhancement of the energy efficiency of PCM-wallboards in comparison with a traditional concrete, especially for the case of the bilayer wallboard