Boiling heat transfer of nanofluids: The effect of heating surface modification

This work reports a comparative study of nucleate boiling heat transfer with aqueous alumina nanofluids on two specially designed surfaces. The detailed surface characterization before and after boiling reveals that the modification of heating surface geometries is mainly responsible for many contradictory results reported in literature. The enhancement or deterioration of boiling heat transfer by nanofluids is dependent upon different surface modifications that strongly affected by the relative size between particles suspended in the liquid and the heating surface geometry, and their interactions. The surface modification by nanoparticles is an inherent feature of nanofluids, and would occur each time after boiling. The experimental results would be affected by the number and frequency of the usage of boiling surfaces. (C) 2010 Elsevier Masson SAS. All rights reserved.