Thermal Properties of Phase Change Materials

This contribution deals with a study of the thermal properties of systems which consist of different types of materials: poly(methyl methacrylate) (PMMA), thermal insulator , and phase change material . The aim of this study is to evaluate the ability of these materials to decrease the working temperature of solar cells and therefore to increase their quantum efficiency. Step-wise and pulse transient methods were used for the determination of thermal parameters, such as the thermal conductivity, thermal diffusivity, specific heat, heat source quality, and heat losses. For the calculation of thermophysical parameters, a fractal theory of physical fields was used. For the determination of the parameters of the fractal model, a multi-parametric regression method was used. The experimental and theoretical results are in good agreement.