As semiconductor devices are driven towards higher powers and faster speeds, they require more capable thermal management technologies. This has led to the use of high performance microchannel cooling, but further improvements in heat transfer performance are sought to: 1) improve temperature stability in the coolers, and 2) increase the heat flux limits of microchannels. Boiling is a potential way to limit the temperature in the coolers, reduce coolant usage, and increase internal heat transfer coefficients. However, only a handful of studies have been performed on 2-phase microchannel flows. The Phase I effort is designed to characterize the fluid and heat transfer physics of 2-phase flows in microchannel systems. The proposed work involves an extensive set of flow visualization experiments in silicon microchannels. The experimental work is complemented by analytic interpretation of the results, generating heat transfer and pressure drop correlations for 2-phase flows in micro-ducts. This will provide the needed understanding to support development of design tools for the generation of cooling systems for laser diodes and electronics. This understanding will be demonstrated during the Phase I program through the fabrication of a microchannel cooler optimized for 2-phase flow.
