We report measurements of the viscosity and density of two binary mixtures comprising hexadecane with dissolved carbon dioxide or methane over the temperature range from (298.15 to 473.15) K and at pressures up to 120 MPa. The measurements were conducted at various mole fractions x of the light component as follows: x = (0, 0.0690, 0.5877 and 0.7270) for xCO2 + (1 -x)C16H34 and x = (0, 0.1013, 0.2021, 0.2976 and 0.3979) for xCH4 + (1 -x)C16H34. The viscosity and density measurements were carried out simultaneously using a bespoke vibrating-wire apparatus with a suspended sinker. With respect to the first mixture, the apparatus was operated in a relative mode and was calibrated in octane whereas, for the second mixture, the apparatus was operated in an absolute mode. To facilitate this mode of operation, the diameter of the centreless-ground tungsten wire was measured with a laser micrometer, and the mass and volume of the sinker were measured independently by hydrostatic weighing. In either mode of operation, the expanded relative uncertainties at 95 % confidence were 2 % for viscosity and 0.3 % for density. The results were correlated using simple relations that express both density and viscosity as functions of temperature and pressure. For both pure hexadecane and each individual mixture, the results have been correlated using the modified Tait equation for density, and the Tait-Andrade equation for viscosity; both correlations described our data almost to within their estimated uncertainties.In an attempt to model the viscosity of the binary mixtures as a function of temperature, density and composition, we have applied the extended-hard-sphere model using several mixing rules for the characteristic molar core volume. The most favourable mixing rule was found to be one based on a mole-fraction-weighted sum of the pure component molar core volumes raised to a power γ which was treated as an adjustable parameter. In this case, deviations of the experimental viscosities from the model were within ±25 %.

The study examines incomprssible laminar Poiseuille flow of a non-Newtonian fluid and heat transfer in a cooling convective fixed wall. The third-grade exothermic reactive fluid is stimulated by heat generation, gradient pressure and thermal buoyancy force. The convective exchange of temperature with the ambient takes after Newtons cooling law. Transilation of the formulated equations to the non-dimensional form is done using relevance quantities and solutions to the nonlinear equations are provided by employing Weighted residual techniques. The obtained solutions for the flow rate, energy, flow wall friction and temperature gradient are graphically plotted for the reactive flow system. Numerical validation of results in comparison with the presented method of solution is carried out. The results revealed that some parameters which are strong heat generation or source should be consciously guided to avoid reactive solution blow up in the exothermic system.

In this study, a pressure driven flow of a magnetohydrodynamic steady coupled-flow across a porous layer horizontal bottom plate with buoyancy force is investigated. The heat transfer problem is also examined by taking viscous and Ohmic dissipation and radiation effects in the energy equation into consideration. The velocity and temperature slip boundary conditions are taken at the plate and at the interface of the porous medium and clear fluid, it is assumed that velocity components to be continuous and the jump in shearing stresses. The solutions to the problem are obtained by employing fourth order Runge-Kutta scheme along with shooting technique and the effects of the pertinent parameters entrenches in the flow system are shown graphically and quantitatively discussed. The results shows that an increase in the thermal convection and pressure gradient enhances the flow rate in both region but the effect was great at the clear region than the porous medium region.

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The investigation of dissipative heat and species diffusion of a conducting liquid under the combined influence of buoyancy forces in a moving plate is examined in the existence of magnetic field. The flowing liquid heat conductivity and viscosity are taken to be linearly varied as a temperature function. The governing derivative equations of the problem are changed to anon-linear coupled ordinary derivative equations by applying similarity quantities. The dimensionless model is solved using shooting technique along with the Runge-Kutta method. The outcomes for the flow wall friction, heat gradient and species wall gradient are offered in table and qualitatively explained. The study revealed that the Newtonian fluid viscosity can be enhanced by increasing the fluid flow medium porosity and the magnetic field strength. Hence, the study will improve the industrial usage of Newtonian working fluid.