Thermal performance evaluation of multi-tube cylindrical LHS system

This study presents a numerical performance evaluation of shell and tube type of latent heat storage (LHS) with multiple finned tubes. Erythritol (C4H10O4) as energy storage media and cooking waste oil as HTF are employed in the proposed study. Nineteen finned heat transferring fluid (HTF) tubes are embedded inside the phase change material (PCM) to enhance melting. Numerical thermal performance study of LHS is performed using parameters such as charging time, liquid fraction, transient temperature and stored energy. For the melting process, the inlet working fluid flow rate and temperature are 75 LPM and 138 °C. For the discharging process, the flow rate is kept the same as the melting progresses, whereas, the inlet temperature is set to be 87 °C. The PCM in LHS gets melted completely within 175 min. during the charging process and it consumes 156 min. for the whole solidification process. The impact of operating parameters variations on the melting progress of the PCM is thoroughly studied. Increasing the working fluid inlet temperature and flow rate enhances the melting progress. The numerical results are validated with the experimental data to showcase the reliability of the proposed LHS system. The numerical results indicate reasonable similarity with the practical results with a maximum deviation of about 6.0%. It is observed that the during melting and solidification process, the overall stored and released energies are 27 MJ and 21.6 MJ, respectively.