THERMODYNAMIC MODELING AND EXPERIMENTAL VALIDATION OF FATTY ORGANIC SYSTEMS SOLID-LIQUID EQUILIBRIUM
The development of new phase change materials (PCM) with increasing performances is a major challenge in thermal energy storage applications. We focus here on the screening of biosourced organic PCM, and more precisely on the development of experimental and numerical methods allowing the phase diagrams establishment for multi-component fatty systems.
Numerical modeling of the Solid-Liquid Equilibrium (SLE) allows the prediction of the equilibrium for systems of well documented materials or the correlation to data obtained using standard experimental methods. Although it is an interesting tool, its use and reliability is limited, either by the poor knowledge regarding studied materials or by the lack of experimental data available due to the time-consuming aspect of traditional methods.
In this work, the relevance and accuracy of standard experimental and numerical methods are discussed in the light of experimental results obtained via a fast method based on infrared thermography. It allows determining the phase transitions of many samples in a two to three hours experiment. The performance of a predictive SLE model is evaluated for a simple eutectic system of 1-Hexadecanol + Myristic acid against experimentally adjusted models found in literature, from results obtained using Differential Scanning Calorimetry (DSC) and from the aforementioned method. In addition, a model accounting for systems presenting a peritectic transition is studied and compared to experimental data for a Palmitic + Stearic acids binary system. Limits regarding both presented models are drawn in order to identify forthcoming challenges.