Numerical study of the effect of phase change materials containing multi-walled carbon nanotubes on improving the heat sink performance of electrical equipment

Heat sinks have always played a crucial role in cooling electrical equipment. In this research, in a new approach, paraffin is used as a phase change material according to the suitable phase change temperature range with multi-wall carbon tube nanoparticles homogeneously in a heat sink. AnasysFluent software with finite volume method and PISO algorithm was used to model and solve the governing equations. The melting process of the PCM is numerically investigated in a three-dimensional space by applying three heat fluxes of 10,000, 20,000, and 30,000 watts per square meter, using the enthalpy-porosity method. According to the obtained results during the phase-change process, the addition of nanoparticles with volumetric percentages of 4, 6, and 8% leads to better performance in reducing the phase-change temperature. After the completion of the phase change process, increasing the volume percentage of nanoparticles does not always have a positive effect, and among the proposed options, nanoparticles with a volume fraction of 4% showed the best performance.This improvement is due to the increased conductive heat transfer in the PCM, resulting from reduced viscosity. Overall, adding 8% nanoparticles increases the total melting time by 15% compared to the pure PCM.