Design and modelling of porous gyroid heatsinks: Influences of cell size, porosity and material variation

Abstract

Triply Periodic Minimal Surfaces (TPMS) are rapidly becoming favourable heatsink and heat exchanger topologies over traditional designs and other cellular structures. Their implicitly defined geometries provide increased heat transfer surface areas while maintaining smooth flow paths capable of further enhancement through flow tortuosity. Substantial investigations have been conducted on these structures within the field of thermal management systems, however more research is needed in understanding how design parameters effect flow and heat transfer performance. Cell size is a critical design parameter that sets the scale of these structures; however, little research has been conducted to date. This work attempts to investigate these gaps through a parametric and material study of TPMS gyroid sheets as heatsinks within turbulent flow. Samples of varying cell size and porosity are compared, where thermal and hydraulic performances are normalised against sample specific volume and wetted surface area. It is found that convective performance is agnostic to cell size, but greatly influenced by porosity. These reuslts are further compared against a reference fin heatsink. Performance measures such as thermal resistance (R), Nusselt number (Nu) and enhancement-to-losses (η) saw improvements of up to 53%, 300% and 42%, respectively when compared to the reference geometry. The results of this work may prove useful in further understanding the relationship between design parameters and heat transfer enhancement and help pave the way to meaningful performance optimisation for these structures.