Effects of porosity on effective thermal conductivities of thermal insulation SiC sandwich panels with Schoen-gyroid structure

Abstract

Additive-manufactured silicon carbide (SiC) ceramic panels with triple periodic minimal surfaces (TPMSs) have proven to be efficient thermal insulation structures, particularly under extremely high-temperature conditions. In this study, the Schoen-gyroid structure is investigated, and a theoretical prediction model is developed to achieve a higher effective thermal conductivity of SiC TPMS using a combination of the net heat flow method and Monte Carlo method. The effects of porosity are compared based on the calculated effective thermal conductivities of these SiC TPMS structures. The research reveals that the effective thermal conductivity of SiC TPMS structures is dependent on the porosity level, and the layered structure of additive manufacturing results in high emissivity. A comparison of the porosities ranging from 40 % to 90 % reveals that the porosity rate of the 40 % structure demonstrates better heat dissipation performance. The simulation results of the effective thermal conductivity of the TPMS with a porosity rate of 40 % using the Schoen-gyroid structure confirm the consistency with the experimental measurements.