Three-dimensional Lattice Boltzmann study on structure optimization and heat dissipation performance of pin-fin heat sink integrated with phase change material

Phase change material (PCM) cooling is an excellent approach for reducing the excessive temperature of electronic devices. However, the heat transfer capacity of a heat sink is diminished by the low thermal conductivity of a PCM. Although this issue can be ameliorated by using extended pin-fins and nanoparticles, the latent heat storage capability of a PCM is decreased. To optimize the heat transfer efficiency of PCM heat sink with pin-fins, in this study, the effects of pin-fin shapes (circle, triangle, square, pentagon, hexagon, and octagon), novel arrangements with triangular fins, and the volume fraction of nanoparticles are investigated using the 3D enthalpybased multi-relaxation time lattice Boltzmann method. The results showed that the PCM heat sink with triangular pin-fins exhibited optimal thermal performance due to the largest heat transmission area between the PCM and pin-fins. After conducting optimization research on triangular pin-fin arrangements, the full melt time was shortened by 14.3 % and the heat dissipation power was increased by up to 15.2 %, when compared with the PCM heat sink with triangular pin-fins. Furthermore, nanoparticles with a volume fraction of <0.1 were beneficial for balancing the elevated heat dissipation capacity and reducing the latent heat duration of the nanoenhanced PCM.