Heat Transfer and Flow Behavior of Nanoparticle Enhanced Ionic Liquids (NEILs)

Experimental investigations were carried out to characterize forced convection behavior of Nanoparticle Enhanced Ionic Liquids (NEILs). 1-butyl-3-methylimidazolium bis{(trifluoromethyl) sulfonyl} imide ([C₄mim][NTf₂]) was used as the base ionic liquid (IL) with 0.5% (weight%) loading of Al₂O₃ nanoparticles. Flow experiments were conducted in a circular tube in the laminar flow regime. Convection results from IL without nanoparticles were used as the base line data for comparison with convection results with NEIL. Viscosity and thermal conductivity of the NEIL and base IL were also measured. NEIL displayed superior thermal performance compared to the base IL. An average of 13% enhancement in heat transfer coefficient was found for the NEIL compared with that of the base IL. Probable reasons of these enhancements are discussed in the paper.