This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are (small) systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. [J. Appl. Phys. 81, 6692 (1997)], was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

A Benchmark Study on the Thermal Conductivity of Nanofluids

Basic Ideas.- Systematic Descriptions.- Advanced Approaches.- Convergent Series For Divergent Taylor Series.- Nonlinear Initial Value Problems.- Nonlinear Eigenvalue Problems.- Nonlinear Problems In Heat Transfer.- Nonlinear Problems With Free Or Moving Boundary.- Steady-State Similarity Boundary-Layer Flows.- Unsteady Similarity Boundary-Layer Flows.- Non-Similarity Boundary-Layer Flows.- Applications In Numerical Methods.

Homotopy Analysis Method in Nonlinear Differential Equations

Impact of Cattaneo–Christov heat flux model in flow of variable thermal conductivity fluid over a variable thicked surface

A comparative study of Casson fluid with homogeneous-heterogeneous reactions.

Entropy generation in steady MHD flow due to a rotating porous disk in a nanofluid

Nanofluid flow and heat transfer due to a rotating disk

Exact analytical solutions for heat and mass transfer of MHD slip flow in nanofluids

Solution of the Thomas–Fermi equation with a convergent approach

Heat and mass transfer of unsteady natural convection flow of some nanofluids past a vertical infinite flat plate with radiation effect

Single phase nanofluids in fluid mechanics and their hydrodynamic linear stability analysis

Mustafa Turkyilmazoglu

Papers

Nanofluid flow and heat transfer due to a rotating disk

Exact analytical solutions for heat and mass transfer of MHD slip flow in nanofluids

Solution of the Thomas–Fermi equation with a convergent approach

Heat and mass transfer of unsteady natural convection flow of some nanofluids past a vertical infinite flat plate with radiation effect

Single phase nanofluids in fluid mechanics and their hydrodynamic linear stability analysis