Influence of Pore Structure Parameters of Solid Thermal Storage Bricks on the Heat Storage/Release Performance

The solid thermal storage device with the electric heating can realize power peak shaving by converting low-valley electricity into heat energy, which is of great significance to reducing environmental pollution and improving energy utilization. Based on the principle of fluid-solid coupling heat transfer, the thermal storage/release process of solid heat storage units with different pore structures were simulated, and the effects of parameters such as the duct structure of heat storage brick and inlet air velocity on the thermal storage/release performance of heat storage units were analyzed and compared. The simulation results show that compared with the heat storage units without rectangular channel, the average temperature and temperature rise rate of the heat storage units with rectangular channel decrease, and the heat exchange with air increases. In the heat release stage, the temperature drop rate of the heat storage units with rectangular channel increases, the heat exchange with air increases, and the heat release is more sufficient. In the process of thermal storage/release, with the increase of the width to height ratio of rectangular channel, the temperature distribution of heat storage units becomes more uniform. In the process of heat release, the smaller the inlet air flow rate and the width to height ratio of rectangular channel, the slower the heat release rate, the longer the heat release time is. When the inlet air velocity is 1.5 m/s, the heat release of model 1 is 33.5 h, and that of model 4 is 18.2 h.