Characterizations of Nanofluid Heat Transfer Enhancements

Abstract

Nanoparticle morphology is thought to be an important factor influencing heat and mass transfer rates in liquid systems. How nanoparticles mechanistically increase heat and mass transfer rates is not well understood. Both dispersed nanoparticles and aggregated nanoparticles are thought to play important roles. Dispersed nanoparticles and associated nanoparticle Brownian movements are purported to cause the enhancements by mixing mechanisms whereas aggregated nanoparticles are purported to cause enhancements by forming highly conductive paths. In this study, morphologies of nanoparticle were quantified in laboratory studies and related to laboratory measured heat and mass transfer rates. No mass transfer enhancements were found in the presence of nanoparticles. Thermal conductivity could be predicted with effective medium theory when aggregated nanoparticle aspect ratio was considered.

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Document Details

Document Type
Technical Report
Publication Date
Sep 06, 2013
Accession Number
ADA590127

Entities

People

  • Drew W. Johnson

Organizations

  • University of Texas at San Antonio

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Air Force
  • Chemical Engineering
  • Chemical Synthesis
  • Chemistry
  • Dielectric Polymers
  • Ecology
  • Electron Microscopy
  • Fullerenes
  • Heat Transfer
  • Mass Transfer
  • Materials Laboratories
  • Materials Science
  • Materials Testing
  • Measurement
  • Metal Oxide Nanoparticles
  • United States
  • Viscous Flow

Readers

  • Combustion and Flow Dynamics.
  • Nanocomposite Materials Science
  • Systems Analysis and Design

Technology Areas

  • Biotechnology