MS Thesis Presentation by Nurudeen Olayiwola
Wednesday, June 22, 2005

(Dr. S. Mostafa Ghiaasiaan, Chair)

"Boiling Heat Transfer in Mini and Micro-channels"

Abstract

Cooling systems that consist of mini-channels (hydraulic diameters in the 0.5 mm to 2.0 mm range) and micro-channels (hydraulic diameters in the 100 µm-500 µm range) can dispose of extremely large volumetric thermal loads that are well beyond the feasible operating 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. Although forced flow boiling in mini and micro-channels has been investigated by several research groups in the past, a verified and reliable predictive method is not yet available.

In this study, the capability of a large number of forced flow boiling heat transfer correlations for application to mini channels is examined by comparing their predictions with three experimental data sets. The data all represent recently-published experiments with mini-channels. The tested correlations include well-established methods for forced-flow boiling in conventional boiling systems, as well as correlations recently proposed for mini-channels.

Based on these comparisons, the most accurate existing predictive methods for mini-channel boiling are identified. The deficiencies of the predictive methods and the potential causes that underlie these deficiencies are also discussed.