2-D and 3-D modulated porous coatings for enhanced pool boiling

Min D. H. , Hwang G. S. , Usta Y., Cora O. N. , Koc M., Kaviany M.

INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, cilt.52, ss.2607-2613, 2009 (SCI İndekslerine Giren Dergi) identifier identifier


A new fabrication method (hot-powder compaction) is developed to readily make 2-D and 3-D modulated coatings for enhanced pool-boiling performance. The modulated coatings are 2-D and 3-D stacks with different height, width, and pitch (modulation wavelength), and made with different particle diameters and porosities. The maximum measured critical heat flux (q(CHF)) of 2-D and 3-D modulated coatings are 3.3 and 2.0 times that of the surface without coatings (plain). As expected from the hydrodynamic stability theory, the experimental results for 2-D coatings are similar to 3-D coatings and show that q(CHF) strongly depends on the modulation wavelength, while particle diameter and porosity have a little effects. The results also suggest that a stack aspect ratio (height to pitch) larger than unity is needed for modulation enhancement of the critical heat flux. (C) 2009 Elsevier Ltd. All rights reserved