Experimental evaluation of electrical conductivity of ionanofluids based on water–[C2mim][CH3SO3] ionic liquids mixtures and alumina nanoparticles

Abstract

Ionic liquids are one of the recent options for heat transfer enhancement due to their excellent features; nevertheless, their thermophysical and electrical properties estimation is a very challenging research goal. In the last years, several studies considered the addition of nanoparticles in the ionic liquids, thus resulting in better heat transfer fluids, with an increased thermal conductivity. However, a complete characterization of ionic liquids and their respective suspensions (termed in the literature as ionanofluids) lacks of a comprehensive approach. In this idea, the present paper debates about the electrical conductivity, offering also a larger point of view by combining both electrical and thermal conductivity, that was previously discussed. Summarizing, this is an experimental study of the electrical conductivity variation with temperature of an ionanofluid involving Al2O3 nanoparticles suspended in a mixture of water and 1-ethyl-3-methylimidazolium methanesulfonate [C2mim][CH3SO3] ionic liquid. Results showed that the electrical conductivity of water–ionic liquid mixture is higher than that of each fluid and the electrical conductivity is diminishing up to 60% by adding nanoparticles to the base mixture. Plus, several correlations are proposed for describing the complex variation of electrical conductivity with both temperature and mass fraction of alumina nanoparticles.