Thin film evaporation on microstructured surfaces — Application to cooling high heat flux electronics

Abstract

A model was developed to simulate the performance of a microgrooved surface undergoing steady thin film evaporation subject to a specified superheat on the groove wall. A theoretical thin film model was coupled with a meniscus curve model to accurately model the complete system. A numerical routine was successfully implemented to solve the governing non-linear differential equations of an evaporating thin film subject to a specified set of groove wall superheat and fluid/interface properties. The resulting thin film profile was used to correlate the heat transfer characteristics as a function of radius of curvature of the intrinsic meniscus. These correlations were then used by another numerical routine to solve for the meniscus curve profile as a function of groove geometry and fluid properties. The total heat, wetted length, heat transfer coefficient, and if desired, 3-D surface plot of the liquid bulk in the microgroove were then extracted from the results. The model results were then compared to the available experimental results. Results of the preliminary comparison with the experiments, as well as future planned tasks, are discussed in this paper.