Numerical Modelling of Sensible Heat Storage Using Rock Beds

Sensible Heat Storage (SHS) is the most advanced and commonly used type of Thermal Energy Storage (TES), where heat is stored by raising the temperature of the storage medium without a phase change. In SHS systems, the amount of energy stored is determined by specific the specific heat capacity of the materials, mass of the storage medium, economic feasibility, and the temperature difference between the initial and final states. Water, as an SHS material, is often used due to its high specific heat capacity and makes thermal energy storage efficient. Solid materials, such as concrete, brick, and rock, are widely utilized for the thermal mass temperature regulation in buildings. However, there is still insufficient work done on solid materials, showing that further investigation is required. Therefore, in this study we focused on the CFD modelling of rock based sensible heat storage system. In this study, charging and discharging simulations are carried out with time depended solver configuration to demonstrate temperature variation, sensible enthalpy and stored energy in the storage medium. According to the results, the maximum values of sensible enthalpy and stored energy were about 35 kJ/kg and 1000 kJ respectively.