Effect of Micro-channel Cross-section and Coolant Pressure on Two-Phase Cooling

Abstract

Inter-chip cooling, where a liquid coolant is passed between the layers of stacked chips, is an enabling technology for realizing significant computational performance improvements through three-dimensional (3D) integration of microelectronic components. The development of this cooling technology requires high fidelity thermal models to evaluate the device and system performance under different cooling configurations and operating environments. In this work, a high fidelity Eulerian multiphase model, previously developed by the author, for predicting two-phase flow and heat transfer behavior in parallel micro-channels, micro-pin fields and radial expanding channels populated with micro-pins, was applied to study the effects of micro-channel cross-section and coolant pressure on two-phase cooling. Results indicated that compared to uniform cross-section microchannels, expanding channels help reduce the pressure gradient along the microchannel and thereby, reduce the saturation and junction temperature variability along the channel. Moreover, inlet orifices help with coolant flashing resulting in reduced convective thermal resistance and wall superheat near the channel inlet.