Thermophysical Characterization of a Thermoregulating Interior Coating Containing a Bio-Sourced Phase Change Material

Abstract

This paper presents the work carried out as part of a study of a proactive interior coating based on both plaster and a phase change material (PCM), intended to improve the energy efficiency of buildings. This bio-based PCM is composed of a mixture of vegetable oils, methyl stearate, and methyl palmitate micro-encapsulated into polymer capsules. These components with distinct thermal properties constitute a mixture that displays supercooling and proves difficult to characterize using methods known in the literature. This article focuses on the thermophysical characterization (i.e., thermal conductivities, thermal capacities, latent heat, melting temperatures) and numerical modeling of a sample of this coating tested in the laboratory. This characterization is derived from experimental measurements carried out on a fluxmeter bench and by inverse methods. A new model of PCM composite characterization is presented and simulated using Python; the output shows a high degree of accuracy in describing the thermal behavior of the coating, regardless of the thermal stress applied, even making it possible to represent the phenomenon of supercooling or partial melting/solidification.