Numerical Study of the Transient Melting Of Nano-Enhanced Phase Change Material

In this study, a non-dimensional parametric numerical study of heat transfer during the melting process within an enclosure filled with a phase change material (PCM) was numerically performed. The enclosure contains a flush mounted heat source mounted on a substrate in the center of its bottom wall. All the enclosure walls are considered adiabatic. The heat source simulates an electronic component (microprocessor) and the substrate acts as a motherboard. Attention was paid to reveal the effect of dispersing copper nanoparticles within the PCM on the thermal and hydrodynamic behavior of the optimized heat sink. For this, a two-dimensional mathematical model based on the conservation equations of mass, momentum and energy was developed. The governing equations were integrated and discretized using the finite volume method. The SIMPLE algorithm was adopted for velocity-pressure coupling. After optimization, copper nanoparticles are dispersed inside the PCM enclosure to check their ability to improve the heat source working time and the melting fraction. The combination of copper nanoparticles and conducting wall (substrate) are tested to improve the heat transfer within PCMs characterized by their low thermal conductivity. Based on the asymptotic computational fluid dynamics technique, correlations were used to predict the maximum safe operating time and the plateau temperature given their practical and technical importance in the manufacture of passive coolers.