The effects of topological configuration and geometric parameters on heat transfer and fluid flow characteristics of lattice-based heat sinks

Abstract

Traditional pin-fin heat sinks could provide only thermal exchange. Whereas the topology and geometry of lattice-based heat sinks make them suitable for simultaneous thermal and structural applications. In this work, we numerically demonstrate the convective heat dissipation performance of periodic pyramidal and tetrahedral lattice-based heat sinks. The motivation for the study is to discover the effects of topological and geometrical parameters of the lattice structure on the heat and fluid flow characteristics of lattice-based heat sinks which are not yet presented in the literature. Hence, we consider pyramidal and tetrahedral lattice topologies with two different L/D ratios (8.8 and 5). Three-dimensional numerical simulations based on the finite volume method were carried out at constant pumping power with water as a coolant for applied heat flux in the range of 10–50 W/cm2. The thermo-hydraulic performance is characterized by the efficiency index and area goodness ratio as a function of pumping power in the laminar regime. The convective heat transfer coefficient values range from 2129 to 6510 W/m2 K for the operating conditions considered in this study. Also, in terms of overall combined thermo-hydraulic performance, the tetrahedral heat sink with the L/D ratio of 5 was found to be 50–53%, 18–25%, and 22–30% more efficient than the P8.8, T8.8, and P5 heat sinks, respectively, for the range of pumping powers considered. The thermo-hydraulic characteristics presented in this study enable the design of lattice-based heat sinks for specific applications with collective pressure drop and heat transfer constraints.