A hybrid methodology for the determination of the effective heat capacity of PCM enhanced building components

This paper presents a new hybrid methodology for the determination of the effective heat capacity (Ceff) of phase change materials (PCMs) for use in numerical models. The methodology focuses on PCM enhanced building panels utilizing a heat flow meter apparatus (HFMA) operating in dynamic mode and a numerical model based on the effective heat capacity method. It comprises of: a) experimental analysis of the panel by means of differential scanning calorimetry (DSC) and HFMA for the estimation of initial Ceff curves, b) optimization of the initial Ceff curves with an algorithm incorporating the numerical model and c) validation of the obtained results. Starting from a complete description of the concept and its main elements, the proposed approach has been successfully employed for the determination of Ceff curves of a lightweight building component combining insulation with thermal storage properties. The derived curves yielded more accurate results when incorporated in the numerical model than the respective curves measured by means of DSC. Simulations of the thermal performance of the building component in different conditions than those used for the determination of the curves validated the effectiveness of the methodology.