contributor author | Hyungdae Kim | |
contributor author | Ho Seon Ahn | |
contributor author | Moo Hwan Kim | |
date accessioned | 2017-05-09T00:38:56Z | |
date available | 2017-05-09T00:38:56Z | |
date copyright | June, 2010 | |
date issued | 2010 | |
identifier issn | 0022-1481 | |
identifier other | JHTRAO-27889#061501_1.pdf | |
identifier uri | http://yetl.yabesh.ir/yetl/handle/yetl/143839 | |
description abstract | The pool boiling characteristics of water-based nanofluids with alumina and titania nanoparticles of 0.01 vol % were investigated on a thermally heated disk heater at saturated temperature and atmospheric pressure. The results confirmed the findings of previous studies that nanofluids can significantly enhance the critical heat flux (CHF), resulting in a large increase in the wall superheat. It was found that some nanoparticles deposit on the heater surface during nucleate boiling, and the surface modification due to the deposition results in the same magnitude of CHF enhancement in pure water as for nanofluids. Subsequent to the boiling experiments, the interfacial properties of the heater surfaces were examined using dynamic wetting of an evaporating water droplet. As the surface temperature increased, the evaporating meniscus on the clean surface suddenly receded toward the liquid due to the evaporation recoil force on the liquid-vapor interface, but the nanoparticle-fouled surface exhibited stable wetting of the liquid meniscus even at a remarkably higher wall superheat. The heat flux gain attainable due to the improved wetting of the evaporating meniscus on the fouled surface showed good agreement with the CHF enhancement during nanofluid boiling. It is supposed that the nanoparticle layer increases the stability of the evaporating microlayer underneath a bubble growing on a heated surface and thus the irreversible growth of a hot/dry spot is inhibited even at a high wall superheat, resulting in the CHF enhancement observed when boiling nanofluids. | |
publisher | The American Society of Mechanical Engineers (ASME) | |
title | On the Mechanism of Pool Boiling Critical Heat Flux Enhancement in Nanofluids | |
type | Journal Paper | |
journal volume | 132 | |
journal issue | 6 | |
journal title | Journal of Heat Transfer | |
identifier doi | 10.1115/1.4000746 | |
journal fristpage | 61501 | |
identifier eissn | 1528-8943 | |
keywords | Nanoparticles | |
keywords | Boiling | |
keywords | Evaporation | |
keywords | Nanofluids | |
keywords | Pool boiling | |
keywords | Water | |
keywords | Critical heat flux | |
keywords | Wetting (Surface science) AND Mechanisms | |
tree | Journal of Heat Transfer:;2010:;volume( 132 ):;issue: 006 | |
contenttype | Fulltext | |