Thermal conductivity enhancement of aqueous ionic liquid and nanoparticle suspension

Abstract

In the present study, the thermal conductivities of ionic liquid + water in the concentrations 0.1-0.6 %w/w and temperatures (302.5-337.9 K) are determined. The thermal conductivity of aqueous 1-butyl-3-methylimidazolium bromide declined with increasing concentration and temperature. A quadratic model is developed for predicting the thermal conductivity of aqueous ionic liquid using response surface methodology with R2 = 0.99. A two-layered feed forward back propagation neural network 2-10-1 is also modeled with mean square error, root means square and absolute average error percentage of 0.005, 0.071 and 2.684, respectively. The thermal conductivity of nanofluid (γ-Al2O3/water) is estimated and compared with the ionic liquid solution at the same concentration and temperature range. Thermal conductivity enhancement ratios of aqueous ionic liquids are found to be more than nanoparticle suspensions.