Computational and Experimental Investigations of Forced Convection in 3D Printed Architected Heat Sinks Based on Triply Periodic Minimal Surface Topologies

Abstract

In this thesis, experimental and computational investigations were carried out to characterize the hydraulic and thermal performances of a triply periodic minimal surfaces (TPMS)-based heat sinks under forced convection, namely; Gyroid sheet-networks (G-Sh), Gyroid solid-networks (G-So), and Diamond solid-networks (D-So) The commercial CFD code STAR-CCM+ was used for the computational investigation. Three different viscous models were implemented to investigate the hydraulic performance of the TPMS structures, namely, laminar model, the SST k-omega, and the realizable k-epsilon. A square airflow channel was used to obtain the hydraulic characteristics such as the permeability (K) and the inertial resistance coefficient (cF) where the Reynolds number was varied between 670-5100 for the experimental investigation and 4080-65000 for the numerical investigation. The thermal characteristics such as the overall convection heat transfer coefficient (UA) Nusselt number (Nu) were investigated computationally based on a validated model. The Realizable k-ε turbulence model was employed to model the flow and heat transfer. The results showed that the structures with the largest pore size exhibited the highest pressure drop values. G-Sh had the highest pressure drop values followed by D-so and then G-So. In addition, the structures that exhibited the highest pressure drop values had the highest U. The G-So and the D-So reported lower permeability-based friction factor compared to metal foams. The Colburn j-factor and the efficiency index (η) were used. The Diamond solid-networks reported the highest compromise between heat transfer and pressure drop.

Date of Award	May 2020
Original language	American English