Thermal performance of plate fin heat sinks with dual-height fins subject to natural convection

In this study, the thermal performance of plate fin heat sinks with dual-height fin profile subject to natural convection is considered. The effect of dual-height configuration, fin spacing and channel length on the thermal performance of the heat sink is investigated numerically. The results show that the thermal performance of the dual-height heat sink monotonically decreases as the secondary fin height decreases for a fixed value of the primary fin height. However, the thermal performance per unit mass can be enhanced by decreasing the secondary fin height, suggesting that the dual height heat sink can be considered for various practical applications where the mass of heat sink determines the value of products. It is also shown that there is a threshold value of primary fin height below which the thermal performance of dual height heat sink decreases as the secondary fin height decreases. This threshold value is shown to linearly decrease as the channel length increases. (C) 2017 Elsevier Ltd. All rights reserved.