Thermophysical Properties of Nanoparticle-Enhanced Ionic Liquids (NEILs) Heat-Transfer Fluids

Abstract

An experimental investigation was completed on nanoparticle enhanced ionic liquid heat transfer fluids as an alternative to conventional organic based heat transfer fluids (HTFs). These nanoparticle-based HTFs have the potential to deliver higher thermal conductivity than the base fluid without a significant increase in viscosity at elevated temperatures. The effect of nanoparticle morphology and chemistry on thermophysical properties was examined. Whisker shaped nanomaterials were found to have the largest thermal conductivity temperature dependence and were also less likely to agglomerate in the base fluid than spherical shaped nanomaterials. INTRODUCTIONIn many solar energy systems, such as concentrating solar power (CSP), there is a drive to operate at higher temperature to reach efficiency limits. This is often limited by the heat transfer fluids working window; it is desirable to have low temperature stability and expand the upper operating temperatures of the fluid. The current generation of organic heat transfer fluids, such as Therminol VP-1

Effect of formation of “long range” secondary dendritic nanostructures in molten salt nanofluids on the values of specific heat capacity

“…Chieruzzi et al [24] reported that dispersion of SiO 2 /Al 2 O 3 /TiO 2 nanoparticles in binary-salt mixtures (NaNO 3 -KNO 3 ) enhanced the specific heat capacity by 20%. Similar trends in the enhancement of specific heat capacity were also reported in various literature reports involving other types of molten salt nanomaterials [23,24,30,31,32] and a separate class of nanofluids which are termed as ''nanoparticle enhanced ionic liquids'' (NEIL) [33][34][35][36][37].…”

Experimental investigation of natural convection heat transfer of Al2O3 Nanoparticle Enhanced Ionic Liquids (NEILs)

“…But the same higher viscosity of NEILs with spherical nanoparticles compare to whiskers nanoparticles was reported by E. B. Fox et al [25], where they have presented optical micrograph of NEILs and have seen that the whiskers particle cluster diameter was smaller than the spherical particles. Fig.…”

Thermally stable bis(trifluoromethylsulfonyl)imide salts and their mixtures

“…1 However, for many prospective applications in which the extremely low vapour pressure of ILs would be of great advantage, e.g. as heat transfer media, 2 in high temperature catalysis 3 or in separation processes, 4 their limited long-term operational stability at temperatures above 250 1C has been found to be a serious limitation. 5 The upper operational temperature limit of IL utilization is defined by both IL thermal decomposition and IL evaporation processes.…”