On the rough hard-sphere-based model for transport properties of nanofluids

Abstract

A semi-theoretical model based on rough hard-sphere (RHS) theory has been employed to correlate and predict the transport properties of 10 nanofluids. The proposed model comprises smooth hard-sphere taken from modified Enskog's theory and a coupling parameter of translational and rotational motions. The molecular scaling constants to be used in new RHS model have been taken from previously developed perturbed hard-sphere equation of state (Hosseini, S.M., Alavianmehr, M.M. and Moghadasi, J., Fluid Phase Equilibria, 423, (2016) 181–189). The new idea of the present study is to introduce a nanoparticle concentration-dependent function into the RHS expression of transport property of the base fluid. The performance of model has been checked by correlating the atmospheric (0.1 MPa) dynamic viscosities and thermal conductivities over the temperature range within 283–343 K. From 539 experimental data points examined, the average absolute relative deviation (AARD) of the correlated and predicted dynamic viscosities was found to be 2.80%. In the case of thermal conductivities, the RHS-based model correlated and predicted 201 experimental data points with AARD equal to 2.47%.