Comparative Study between Experimental Analysis and CFD Software Analysis of PCM material in Thermal Energy Storage System

Abstract

In this Research work, phase change materials are used to store heat energy, which can be utilized for Cold start in automobiles. Various PCMs like Paraffin wax, sodium acetate tri-hydrate and phenolphthalein are considered which are used to absorb heat from the coolant water from the engine. The conduction and convection criterion of heat transfer enable the PCM to store this heat as latent heat. The temperature change and thereby heat absorbed by the PCM is first studied experimentally. Then the amount of convection and temperature change brought about due to the heat flux has been simulated and studied in detail using GAMBIT and FLUENT. The experimental results and the simulation results have been compared and found to be similar. This has enabled us to identify the better PCM relative to the other PCMs which were studied. The world is looking for an alternative to reduce environmental pollution as it has emerged as the most important problem of this century. During Cold start in internal combustion engines, various problems such as increased fuel consumption resulting from heterogonous combustion, increasing concentration of toxins in emissions, increase in lubricant viscosity and resistance to motion and thereby increase in load on the accumulator and starter resulting in increased vibration and noise. Energy storage plays a critical and vital role in enhancing performance and reliability of Thermal Energy Systems. Developments of new devices that solve this problem are a necessity. Thermal energy storage system (TESS) is one such device. The TESS uses Phase Change Material's (PCM) latent heat storage capacity for pre-heating the internal combustion engine. The thermal energy storage device (TESD) works on the effect of absorption and rejection of heat during the solid-liquid phase change of heat storage material. The overall function of the TESS is dominated by the PCM. The PCM material should be selected considering the application and the working conditions. Depending on the applications, the PCMs should first be selected based on their melting temperature. Materials