Numerical investigation on heat transfer enhancement of graphene coated circular pin fin

The benefit of the graphene coating is twofold. Firstly, the lower temperature on the graphene coated pin fin can be attained, thus ensuring the application system to operate at lower temperatures, preventing overheating. Secondly, the graphene coated fin could yield more uniform distribution of temperature along the pin fin, thereby producing a more uniform heat dissipation along the fin. With such a coating, an improved cooling system can be created, in alleviating the heat transfer limit of conventional heat sink. Numerical results reported in this study revealed that the graphene coating is consistently beneficial for heat dissipation for all cases investigated, regardless of the air velocity, coating thickness, and pin fin length. At the longest pin fin examined, which is 25D, the temperature difference between the base and the tip of the pin fin can be reduced to 1.70K, as compared to 10.60 K temperature difference for the conventional pin fin. Additionally, thermal resistance reduction of up to 56.60% can be attained using the graphene coating technique.