CFD simulation of thermal dissipation from fan-added plate fin and offset strip fin heat sinks

In the present study, we have performed two-dimensional CFD simulations on thermal dissipation from isothermal plate fins and offset strip fins with a specific DC fan. Computations are implemented on a single flow passage between fins due to the periodicity in the lateral direction, and analysis of thermal performance is carried out for a heat sink for CPU cooling with a width of 60 mm and a length of 65 mm. As anticipated, the offset strip fin leads to 35% higher Nusselt number at each fin surface compared to the plate fin. However, the optimum OSF heat sink has 42% wider fin pitch to compensate for increased pressure drop, which results in smaller fin surface area than the plate fin heat sink. Consequently, the overall thermal performance of the offset strip fin heat sink is about 4% lower than that of the plate fin heat sink considered in this study, irrespective of the enhanced surface geometry.