The objective of this paper is twofold: First, a computational model is presented for predicting the thermal behavior of a packed bed LHTES unit consisting of spherical capsules containing PCM with HTF flowing across them. Second, parametric studies are performed to access the effects of geometric and operating parameters on the thermal behavior of the system

The developed model can be used to predict the energy storage behavior of different phase-change materials used with different heat transfer fluids, flow rates and temperatures. Numerical solutions have been obtained for the case where the phase change material is Paraffin wax [RT60] and the heat transfer fluid is water.