C.M. Brown, L. Cristofolini, et al.
Chemistry of Materials
This article is the second part of a study on flow boiling of R236fa and R245fa. This part presents the heat transfer coefficients obtained in a 12.7mm silicon evaporator composed of 135 microchannels with 85μm wide and 560μm high channels separated by 46μm wide fins. There were 35 local heaters and temperature measurements arranged in a 5×7 array. The heat transfer results were uniform in the lateral direction to the flow (attributable to the inlet restriction) and a function of the heat flux, vapor quality and mass flux. The steady-state standard deviation of the local base temperature was less than 0.2°C, inferring that the boiling process was very stable. For wall heat fluxes over 45kW/m2, the heat transfer coefficient curves were V-shaped, decreasing for intermittent flow regimes and increasing for annular flow. The three-zone model of Thome et al. (2004) was the best heat transfer prediction method when setting the dryout thickness equal to the channel roughness. © 2011 Elsevier Inc.
C.M. Brown, L. Cristofolini, et al.
Chemistry of Materials
L.K. Wang, A. Acovic, et al.
MRS Spring Meeting 1993
Kafai Lai, Alan E. Rosenbluth, et al.
SPIE Advanced Lithography 2007
Julian J. Hsieh
Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films