Medium-temperature phase-change materials thermal characterization by the T-History method and differential scanning calorimetry

This paper presents a thermal characterization of salt mixtures applying the T-History method (THM) and the differential scanning calorimetry (DSC) techniques. By using water as a standard substance, the original THM was developed to analyze materials with melting points under 100°C. This is the first research that proposes to replace water by glycerin to characterize medium-melting-temperature phase-change materials (PCMs) (140–220°C). Moreover, the DSC technique was used to validate and compare the results obtained with the THM for each mixture. For instance, the system compound of 40% KNO₃–60% NaNO₃ was studied, and the enthalpy of fusion determined by THM and DSC differs by 2.1% between each method. The results given by the two methods for all mixtures showed that both techniques are complementary and present satisfactory agreement with the specialized literature.