Performance of the Cold Latent Storage System

냉열잠열축열조의 성능해석

The performance of the cold latent heat storage is investigated by experiment and by a simplified analytic approach. The heat storage tank has eight horizontal circular tubes and one path of refrigerant evaporating tube. The phase change material in the heat storage tank is water which is frozen by evaporating refrigerant of refrigeration system and melts by the warm air in the heat storage tank. In the experiment, the performance has been studied by the various conditions including the initial water temperature on solidification and flow rate and temperature of air. The rate of recovered heat has been simulated by a simplified model and the results shows a good agreement. In solidification process, initial water temperature causes time delay corresponding to the sensible heat and it is found that the shape of evaporator is important. In melting process, the recovered heat rate from the heat storage tank is proportional to $Re^{0.8}(T_{bi}-T_f)$ of air where $T_{bi}$ and $T_f$ indicate temperatures of inlet air and phase change, respectively. And the deminishing rate of the recovered heat is higher for the higher heat rate.