Thermal energy storage is needed to improve the efficiency of solar thermal energy applications (STEA) and to eliminate the mismatch between energy supply and energy demand. Among the thermal energy storages, the latent heat thermal energy storage (LHTES) has gained much attention because of its high-energy densities per unit mass/volume at nearly constant temperatures. This review presents previous studies on the numerical modeling of phase change materials (PCMs) through a commercial computational fluid dynamic (CFD) software and self-developed programming to study the heat transfer phenomena in PCMs. The CFD (Fluent) software is successively used to simulate the application of PCMs in different engineering applications, including electronic cooling technology, building thermal storage, and heating, ventilation, air conditioning (HVAC). Using CFD software to design LHTES is believed to be an effective way to save money and time and to deliver optimization tools for maximum efficiency of STEAs.