Experimental evaluations and computational fluid dynamics simulations for heat transfer property and pressure loss of lattice-structured heat sinks

Abstract

It is expected that lattice-structured heat sinks, which can be fabricated by metal additive manufacturing (AM) technologies, are applied to thermal management components such as heat sinks. In this study, lattice-structured heat sinks consisting of various unit cells (BCC, Octet, Kelvin, Cube) were fabricated by laser powder bed fusion, which is one of the AM processes. The heat transfer characteristics (Nusselt number and Darcy friction factor) of the lattice-structured heat sinks under forced convection were experimentally evaluated using small-sized wind channel equipment. In addition, computational fluid dynamics (CFD) simulations were performed under the same conditions as experiments to validate the CFD simulations and evaluate the fluid flow and heat transfer inside the lattice structures. The CFD simulation roughly reproduced the Nusselt number (Nu) and Darcy friction factor (f) measured by experiments. The unit cell morphology did not significantly affect Nu but contributed to f. The Octet and Kevin unit cells exhibited larger f than BCC and Cube unit cells.