Investigation On Preparation And Heat Transfer Of Fatty Acids As Phase Change Materials

Phase change materials(PCMs)are the energy storage materials that have considerably higher thermal energy storage densities, and are able to absorb or release large quantities of energy at a constant temperature by undergoing a change of phase.In this paper, phase-change thermal insulating materials were prepared by adding shape-stabilized PCMs,which were fabricated by porous materials absorbing organic PCMs physically, and the application of this novel insulating material in building structures was also evaluated.This paper first of all kinds of single the fatty acids thermal physical test, analyze the phase transition temperature and phase change of latent heat. In order to overcome the shortage of single fatty acids, expand the scope of application of fatty acids, and study the two yuan a eutectic mixture fatty acids, through the theoretical prediction formula to16kinds of a eutectic mixture phase transition temperature and phase change of latent heat and ratio and the calculation according to their melting point distribution analysis of the potential engineering application. Then will the theoretical prediction results and the experimental results were compared and verify the accuracy of the calculation of theory, also identified eutectic mixture of phase change of temperature and the latent heat. Use the ir spectrometry judgment eutectic mixture presence of any new substance, nature is stable.through the adsorption preparation phase change plasterboard, according to the phase change materials in the adsorption quantity and shelter a matrix of the form, determined the best preparation process; And the phase change thermal physical plasterboard, leakage degree, durability and compatibility and so on were studied, and the results show that:to high acid-for palmitic acid of phase change materials of phase change plasterboard temperature was24.63℃phase change, phase transformation of latent heat of45.28J/g, phase transformation temperature of the human body temperature to comfortable.The paper with high acid-for palmitic acid phase change materials for the phase change of the melting process plasterboard. Containing different preparation of quality score of high acid-palmitic acid a eutectic mixture phase change plasterboard, boundary conditions and constant temperature of melting characteristics experiment, obtains the different kind of high acid-palmitic acid phase change plasterboard heating curves, and analyses the heat transfer characteristics of the phase change plasterboard, for future numerical calculation and simulation lay the foundation.Finally, In order to investigate the melting performance of capric acid in rectangular enclosure, numerical simulation by enthalpy-porous model have been carried to study the melting process of capric acid in rectangular enclosure with a heated vertical wall in right side, a experiment also have been done to validate the accuracy of numerical simulation. The simulation shows that average Nusselt decreases gradually with time, but the rate of melting contrary to it. Melting volume fraction is a exponential relationship with Ste,Ra and Fo,which is0.6635、0.1906、0.8535respectively.