Thermofluid characteristics of two-phase microgap coolers

The thermofluid characteristics of a chip-scale microgap cooler, including single-phase flow of water and FC-72 and flow boiling of FC-72, are explored. Heat transfer and pressure drop results for single phase water are used to validate a detailed numerical model and, together with the convective FC-72 data, establish a baseline for microgap cooler performance. Experimental results for single phase water and FC-72 flowing in 120 gm, 260 [mu m and 600 mu m microgap coolers, 3 1 mm wide by 34mm long, at velocities of 0.1-2 m/s are reported. '' Pseudo-boiling '' driven by dissolved gas and flow boiling of FC-72 are found to provide significant enhancement in heat transfer relative to theoretical single phase values.