CFD-Based Investigation of Thermal Behavior in Microchannel Heat Sinks using Supercritical CO2

Abstract

Microchannel heatsinks (MCHSs) are a promising technology for cooling high-power electronic devices. Because of its superior thermophysical qualities, supercritical carbondioxide (sCO₂) is a coolant that has potential to replace water in MCHSs.. This paper presents a CFD-based investigation of the thermal behavior in MCHSs using sCO₂ and comparing it with water. It includes the impact of operating and geometric parameters on thermal resistance, temperature of the heat source, and pressure drop. The results show that sCO₂ can achieve better thermal performance than water in certain operating and geometric conditions. For example, by supplying  constant heat flux of 1.81×〖10〗^6  W/m^2, sCO₂ is capable of reducing thermal resistance upto 30% compared to water. However, sCO₂ also has a higher pressure drop than water, which can lead to higher pumping power requirements. Overall, the study reveals that sCO2 is a promising coolant for MCHSs, especially for applications where high heat flux removal is required. However, careful consideration should be given to the pressure drop and pumping power requirements when designing sCO₂-based MCHSs.