Optimization Study of a Silicon-Carbide Micro-Capillary Pumped Loop

Wide bandgap semiconductors such as SiC and GaN are materials that are advantageous for high power electronic devices. High power devices generate large amounts of energy that must be removed, and traditional cooling methods are insufficient for maintaining the desired operating temperatures. Thus, thermal management methods for high power electronic devices need to be developed. A SiC micro-capillary pumped loop thermal management system is being evaluated to cool SiC high power devices. Mathematical models incorporating two-phase flow and capillary wicking have been developed to analyze capillary pumped loops or loop heat pipes. This investigation uses a model based on the methodology of Dickey and Peterson (1994). The model takes an energy balance on the condenser and evaporator regions, as well as a pressure balance across the meniscus. A parametric study has been performed on the micro-CPL to determine the best design for a p-i-n diode that is less than 1 cm square and which produces a heat flux at the junction of over 300 W/cm². The micro-CPL will be limited to a maximum size of 6.5 cm². The liquid and vapor line lengths, number of grooves, and groove dimensions are varied to determine optimal values. The results and trends of the optimization calculations are discussed.