Separate effects of surface roughness, wettability, and porosity on the boiling critical heat flux

• Main Authors: O'Hanley, Harrison F. (Contributor), Coyle, Carolyn P. (Contributor), Buongiorno, Jacopo (Contributor), McKrell, Thomas J. (Contributor), Hu, Lin-Wen (Contributor), Rubner, Michael F. (Contributor), Cohen, Robert E. (Contributor)
• Other Authors: MIT Materials Research Laboratory (Contributor), Massachusetts Institute of Technology. Department of Chemical Engineering (Contributor), Massachusetts Institute of Technology. Department of Nuclear Science and Engineering (Contributor), MIT Nuclear Reactor Laboratory (Contributor)
• Format: Article
• Language: English
• Published: American Institute of Physics, 2014-05-09T16:18:53Z.
• Subjects: Article
• Online Access: Get fulltext

 The separate effects of surface wettability, porosity, and roughness on the critical heat flux (CHF) of water were examined using engineered surfaces. Values explored were 0, 5, 10, and 15 μm for Rz (roughness), <5°, ∼75°, and >110° for static contact angle (wettability), and 0 and 50% for pore volume fraction. The porous hydrophilic surface enhanced CHF by 50%-60%, while the porous hydrophobic surface resulted in a reduction of CHF by 97%. Wettability had little effect on the smooth non-porous surface CHF. Surface roughness (Ra , Rq , Rz ) had no effect on CHF within the limit of this database.