Heat transfer measurement for flow of nanofluids in microchannels using temperature nano-sensors | |
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Year of publication | 2012 |
Title of paper | Heat transfer measurement for flow of nanofluids in microchannels using temperature nano-sensors |
Authors | Yu, J., Kang, S.-W., Jeon, S., and Banerjee, D. |
Volume | 3(1) |
Pages | 013004 - 1 - 9 |
Journal | Frontiers in Heat and Mass Transfer (FHMT) |
Link | http://dx.doi.org/10.5098/hmt.v3.1.3004 428회 연결 |
Anomalous enhancement of the convective heat flux values were observed for the different experimental conditions. Precipitation of nanoparticles on heat exchanging surfaces was confirmed using materials characterization techniques such as Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray spectroscopy (EDX). It is suggested that moderate precipitation of nanoparticles lead to formation of isolated nanofins which cause the observed enhancements in forced convective heat transfer (due to increase in the effective surface area), while excessive precipitation results in scaling (fouling) of the surface which causes degradation of the heat flux values (compared to that of the pure solvent). This study shows that the surface conditions play a dominant role in determining the efficacy for heat transfer in multi-phase flows – particularly those involving nanoparticle coatings and nanoparticle suspensions (compared to the bulk properties of the test fluid itself). |