Assessment of Flow Boiling Heat Transfer Correlations for Application to Mini-channels

摘要

Cooling systems that consist of mini-channels (channels with hydraulic diameters in the 0.5 mm to 2.0 mm range) and micro-channels (channels with hydraulic diameters in the 100 um-500 urn range) can dispose of large volumetric thermal loads that are well beyond the feasible range of conventional cooling methods. Mini/micro-channel systems that utilize boiling fluids are particularly useful due to the superiority of boiling heat transfer mode over single-phase flow convection. Flow boiling in mini and micro channels has been investigated experimentally by several research groups recently, and a number of empirical correlations have been developed, usually based on only a single set of experimental data.In this study, the capability of a number of widely used forced flow boiling correlations for application to mini channels is examined by comparing their predictions with experimental data from three separate sources. The tested correlations include well-established methods for conventional boiling systems, as well as correlations recently proposed for mini-channels. The experimental data all represent mini-channels. Based on these comparisons, the most accurate existing predictive methods for the tested mini-channel boiling data are identified.