Thermal Conductivity of Ionic Liquids and IoNanofluids and Their Feasibility as Heat Transfer Fluids

Abstract

Ionic liquids and ionanofluids were studied in recent years as possible alternatives to current engineering fluids, namely in the area of heat transfer. Excellent thermal properties, like high heat capacity per unit volume and thermal conductivity, allied to the dispersion of nanoparticles in them, have created great expectations, as the enhancement of their thermophysical properties liquids can contribute to better efficiency in heat transfer. The thermal conductivity of [P66614][N(CN)2], [P66614][Br], [C2mim][SCN], [C4mim][SCN], [C2mim][C(CN)3], and [C4mim][C(CN)3] in the temperature range of 293–343 K at 0.1 MPa and their ionanofluids with multiwalled carbon nanotubes are reported in the present work. While we could not obtain stable suspensions with phosphonium based ionic liquids, thermal conductivity enhancement of cyano-based ionic liquids was compared with our previous work using dicyanamide ionic liquids. The thermal conductivity of C2mim+ ionic liquids and ionanofluids is generally higher than t...