Advanced

Convective heat transfer performance of aggregate-laden nanofluids

Wu, Zan LU and Sundén, Bengt LU (2016) In International Journal of Heat and Mass Transfer 93. p.1107-1115
Abstract
With the recent progress in nanotechnology, nanofluids are emerging as a new class of heat transfer fluids formed by adding nanometer-sized structures (e.g., particles, fibers, tubes) in conventional base fluids (e.g., water, ethylene glycol, engine oil). Due to attractive van der Waals forces, nanoparticles tend to agglomerate to form aggregates in nanofluids to form the so-called aggregate-laden nanofluids. Aggregation affects the nanofluid properties such as thermal conductivity and viscosity and further affects the heat transfer performance. The discrepancies regarding the influence of nanoparticles on thermophysical properties and heat transfer characteristics in the literature might arise due to nanoparticle aggregation. Firstly,... (More)
With the recent progress in nanotechnology, nanofluids are emerging as a new class of heat transfer fluids formed by adding nanometer-sized structures (e.g., particles, fibers, tubes) in conventional base fluids (e.g., water, ethylene glycol, engine oil). Due to attractive van der Waals forces, nanoparticles tend to agglomerate to form aggregates in nanofluids to form the so-called aggregate-laden nanofluids. Aggregation affects the nanofluid properties such as thermal conductivity and viscosity and further affects the heat transfer performance. The discrepancies regarding the influence of nanoparticles on thermophysical properties and heat transfer characteristics in the literature might arise due to nanoparticle aggregation. Firstly, three performance comparison criteria for nanofluids were proposed for thermally developing laminar flow, fully developed laminar flow and fully developed turbulent flow to evaluate the nanofluid efficiency as coolants. Secondly, parametric effects of aggregates on nanofluid viscosity and thermal conductivity were investigated. The cooling efficiency of the aggregate-laden nanofluids depends on aggregate parameters such as aggregate ratios, interfacial thermal resistance, volume fraction of aggregates in nanofluids and volume fraction of nanoparticles in the aggregates. One method to tailor the aggregate morphology is presented by dispersing nanoparticles of different size into a base fluid. By this method, the volume fraction of nanoparticles in the aggregates might increase, which thus enhances the nanofluid effectiveness due to reduction of viscosity. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Aggregate, Nanofluid, Performance comparison criterion, Heat transfer, Thermal conductivity, Viscosity
in
International Journal of Heat and Mass Transfer
volume
93
pages
1107 - 1115
publisher
Pergamon
external identifiers
  • wos:000367107700101
  • scopus:84947996361
ISSN
0017-9310
DOI
10.1016/j.ijheatmasstransfer.2015.11.032
language
English
LU publication?
yes
id
377bcc49-5bde-488a-bdb7-31947fc179a9 (old id 8312406)
date added to LUP
2015-12-16 11:28:05
date last changed
2017-01-01 03:45:20
@article{377bcc49-5bde-488a-bdb7-31947fc179a9,
  abstract     = {With the recent progress in nanotechnology, nanofluids are emerging as a new class of heat transfer fluids formed by adding nanometer-sized structures (e.g., particles, fibers, tubes) in conventional base fluids (e.g., water, ethylene glycol, engine oil). Due to attractive van der Waals forces, nanoparticles tend to agglomerate to form aggregates in nanofluids to form the so-called aggregate-laden nanofluids. Aggregation affects the nanofluid properties such as thermal conductivity and viscosity and further affects the heat transfer performance. The discrepancies regarding the influence of nanoparticles on thermophysical properties and heat transfer characteristics in the literature might arise due to nanoparticle aggregation. Firstly, three performance comparison criteria for nanofluids were proposed for thermally developing laminar flow, fully developed laminar flow and fully developed turbulent flow to evaluate the nanofluid efficiency as coolants. Secondly, parametric effects of aggregates on nanofluid viscosity and thermal conductivity were investigated. The cooling efficiency of the aggregate-laden nanofluids depends on aggregate parameters such as aggregate ratios, interfacial thermal resistance, volume fraction of aggregates in nanofluids and volume fraction of nanoparticles in the aggregates. One method to tailor the aggregate morphology is presented by dispersing nanoparticles of different size into a base fluid. By this method, the volume fraction of nanoparticles in the aggregates might increase, which thus enhances the nanofluid effectiveness due to reduction of viscosity.},
  author       = {Wu, Zan and Sundén, Bengt},
  issn         = {0017-9310},
  keyword      = {Aggregate,Nanofluid,Performance comparison criterion,Heat transfer,Thermal conductivity,Viscosity},
  language     = {eng},
  pages        = {1107--1115},
  publisher    = {Pergamon},
  series       = {International Journal of Heat and Mass Transfer},
  title        = {Convective heat transfer performance of aggregate-laden nanofluids},
  url          = {http://dx.doi.org/10.1016/j.ijheatmasstransfer.2015.11.032},
  volume       = {93},
  year         = {2016},
}