Role of microconvection induced by Brownian motion of nanoparticles in the enhanced thermal conductivity of stable nanofluids
- 1 June 2009
- journal article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 94 (22), 223101
- https://doi.org/10.1063/1.3147855
Abstract
We investigate the role of microconvection induced by Brownian motion of nanoparticles on thermal conductivity enhancement in stable nanofluids containing nanoparticles of average diameters 2.8–9.5 nm. Nanofluids with a fixed particle loading of 5.5 vol . % , the effective thermal conductivity ( k / k f ) increases from 1.05 to 1.25 with increasing particle diameter. Upon increasing the aspect ratio of the linear chains in nanofluids, very large enhancement of thermal conductivity is observed. These findings confirm that microconvection is not the key mechanism responsible for thermal conductivity enhancements in nanofluids whereas aggregation has a more prominent role.Keywords
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