Densities, ρ, viscosities, η, and refractive indices, n D, for binary mixtures of hexane, decane, hexadecane, and squalane with benzene were measured over the whole composition range at 298.15 K and atmospheric pressure. The excess molar volumes, , and viscosity deviations, δη, were calculated from experimental measurements. These result were further fitted to the Redlich−Kister equation to estimate the binary coefficients and standard errors. The effects of chain length and branching of alkanes on and δη values have been discussed.

Densities, ρ, viscosities, η, and refractive indices, n D , have been measured as a function of composition for binary mixtures of cyclohexane, decane, hexadecane, and squalane with hexane at 298.15 K and atmospheric pressure. From these measurements the excess molar volumes, V E m , viscosity deviations, δη, and the change in refractive indices on mixing, ∆n D , were calculated. These results were fitted to Redlick-Kister polynomial equations to estimate the binary coefficients and standard errors. The effects of size and shape of the components on excess properties have been discussed.

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The heat transfer properties of current liquids are specifically improved by suspending nanocrystalline solid elements smaller than 100 nm in diameter. These liquids are considered as potential working fluids for applications such as car radiators, solar collectors, electronic frost systems, nuclear reactors and heat pipes. Due to such uses, here we formulate CuO-H 2 O nanofluids in a two-dimensional circular geometry with a rhombus-shaped barrier maintaining the constant temperature of two adjacent high walls. The streamlines and isotherms have been plotted using the control volume finite element method and applying the KKL model for nanofluid simulation. The results were calculated for different concentrations of nanoparticles, Hartmann number and Rayleigh number. It was found that in a large number of volume fraction and Hartmann number, the isotherms near the outer margin are more prominent while the low-volume-concentration isotherms are concentrated near the adiabatic wall of the obstacle. It was also found that there is a temperature gradient in the radial direction at a higher volume fraction and Hartmann number (Ha). The temperature gradient was limited to adiabatic walls of the obstruction in lower volume fraction and Ha. Two similar shapes but differently directed eddies are formed for any value of Ra in streamlines. |Ψ max | nf increases with an increase in the values of Ra from 10 3 to 10 5 .