Thermal performances of finned heat sink filled with nano-enhanced phase change materials: Design optimization and parametric study

Abstract

The present numerical study proposes a novel heat sink model with combined NANO- enhanced Phase Change Materials (NANOPCM) and pin fins for the thermal management of electronic devices. The governing equations, model the heat transfer and the NANOPCM melting process, resolved by using CFD software (ANSYS Fluent) based on a finite volume method scheme. First, a comparison between heat sink with and without phase change material (PCM) was carried out. Then, different configurations of finned-heat sinks are studied to investigate the effect of 2 key parameters: the pin fin thickness and the pin fin numbers on the performance of the PCM-based heat sink. Furthermore, the effects of nanoparticles: graphene (GNP), copper oxide (CUO), and aluminium oxide (AL2O3) are investigated. The same volume fraction of nanoparticles 1.65%vol (5%wt weight fraction) was adopted to explore the most efficient NANOPCMs. Further, the impact of nanoparticle weight fractions (5%wt and 7%wt) are also detailed.This study demonstrated that the rise of pin fins volume fraction and the nanoparticles concentration don't improve the heat sink performances; the insertion of 9% pin fins volume fraction and the dispersion of 1.65 %vol graphene showed advanced performances (the operating time has been extended by 2.75 times). The results demonstrated also that the nanoparticle dispersion inside the finned heat sink does not have a significant effect on the thermal response due to the high thermal conductivity of the pin fins.