This study presents a simulation of the simultaneous melting and solidification of phase change materials (PCMs) in a triple-tube annular heat exchanger, with the PCMs placed in the middle tube in both single and dual-radial configurations. In the single PCM configuration, the middle tube is filled with one PCM (PCM#2), whereas in the dual-radial configuration, the middle tube is divided radially into two equal volume sections each containing a PCM ((PCM#1 and PCM#3) with different melting point. To maintain a constant hot temperature at the inner surface of the middle tube, hot fluid is circulated through the inner tube, while cold fluid flows through the outer tube to keep the outer surface of the middle tube at constant cold temperature. The PCM consistently melts at the inner surface and solidifies at the outer surface of the middle tube. Computer code was developed and validated against the available data of PCM melting in the literature. Post-validation, simulations were conducted for both fully solid and fully liquid initial conditions in each configuration. The results demonstrate that the dual PCM configuration offers superior energy storage and recovery compared to the single PCM configuration under the given conditions.