Anomalous Size Dependent Rheological Behavior of Alumina Based Nanofluids

  • Singh P
  • Anoop K
  • Patel H
 et al. 
  • 6


    Mendeley users who have this article in their library.
  • N/A


    Citations of this article.


Rheological behaviour of Alumina (Al2O3) based nanofluids (NFs) has been studied and found to be exhibit unexpected behaviour. Two base-fluids viz, water and ethylene glycols (EG). Three particle sizes (11, 45 and 150 nm), varying over an order of magnitude, were used to analyze the effect of particle size. The experimental data has shown typical Newtonian behavior for both W based and EG based alumina NFs The viscosity of EG based NFs is found to be anomalously reduced compared to the base fluid. This reduction in viscosity may be due to hygroscopic nature of EG or due to the presence of water in as-received high concentration sample also, as told by some researchers. However, this phenomenon was absent for water based NFs. The inter-related effects of particle size, concentration and mode of dispersion (mono or poly-dispersed) were investigated. To eliminate the effect of size variation, mono dispersed NFs are obtained by centrifuging and re-suspension of parent NFs. Particle migration under shear is attributed to the reduction of viscosity. The increase in bulk viscosity with particle size reduction is attributed to the surface forces acting between the particles and the medium in a suspension.

Author-supplied keywords

  • alumina suspensions
  • nanofluids
  • rheology of suspensions
  • shear induced particle migration
  • viscosity of suspensions

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Pawan K. Singh

  • K. B. Anoop

  • H. E. Patel

  • T. Sundararajan

  • T. Pradeep

  • Sarit K. Das

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free