![]() ![]() ![]() mol −1) and no very low values of preexperimental factor (−17 ![]() We note that this is called HajKacem-Ouerfelli equation which presents good concordance only for the low and moderate viscous fluids which have no very high values of activation energy ( kJ proposed an empirical power law-type equation for modeling the relationship between the two parameters of viscosity Arrhenius-type equation for some pure classical solvents, such as the Arrhenius energy ( ) or the preexponential factor ( ). Also, for the second parameter, the preexponential factor ( ) can be closely related to the viscosity of the pure system in vapor state at the same studied pressure. In fact, the viscosity Arrhenius energy ( ) can be related to the enthalpy of vaporization ( ) at the same pressure. Indeed, it can be used to estimate the nonavailable value of one parameter using the information provided by the other one. In addition, the suggested practical equation is useful when one of the two Arrhenius parameters data is absent. Also, this will open a field for new theoretical concept and treatment. For that, we will use statistical correlation analysis techniques for determining a relationship between the two viscosity Arrhenius parameters, allowing the reduction of the parameters number and facilitating thus calculations in engineering of fluid transport. This paper aims to contribute to describing the viscosity of pure liquids. Many empirical and semiempirical models have been developed to describe the viscosity of pure liquids and binary liquid mixtures. On the other hand, excess thermodynamic functions (like enthalpy of hydration) and deviations of analogous nonthermodynamic functions (like viscosity) of binary liquid mixtures are fundamental for understanding different types of intermolecular interactions in these mixtures. This is why several models have been proposed in the literature essentially based on Eyring theory or empirical or semiempirical equations that are not always applicable to a large number of mixtures. The theoretical description of viscosity is therefore quite complex. The viscosity of fluids is determined both by collision among particles and by the force fields which determines interactions among molecules. As a result, rigorous and reliable data must be available with models that can provide a reliable estimation of the viscous behavior of mixtures. Most cases found in industrial settings involve the difficulty posed by the nonlinear behavior of mixtures, against the mole fraction of one of the pure components constituting the corresponding binary liquid mixtures. Being one of the most important factors in its own right in transport equations, nutrition, and chemical, cosmetic, and pharmaceutical industries, liquids viscosity parameters are essential for energy transference calculations and for hydraulic calculations of fluid transport. IntroductionĪmong the physicochemical properties of pure liquids and their mixtures that are constantly in demand for optimizing and designing industrial processes is viscosity. In addition, the suggested model is very beneficial for engineering data since it would permit estimating the missing parameter value, if a well-established estimate of the other parameter is readily available. Empirical validations using 75 data sets of viscosity of pure solvents studied at different temperature ranges are provided from previous works in the literature and give excellent statistical correlations, thus allowing us to rewrite the Arrhenius equation using a single parameter instead of two. Then, we introduce a third parameter, the Arrhenius temperature ( ), to enrich the model and the discussion. In the present work, based on statistical techniques for nonlinear regression analysis and correlation tests, we propose a novel equation modeling the relationship between the two parameters of viscosity Arrhenius-type equation, such as the energy ( ) and the preexponential factor ( ). Viscosity is one of the important properties which are affected by pressure and temperature. Where u( r) is the (radially) local axial velocity, dp / dz is the pressure gradient along the pipe, and R is the pipe radius.In transport phenomena, precise knowledge or estimation of fluids properties is necessary, for mass flow and heat transfer computations. In continuum mechanics, a power-law fluid, or the Ostwald–de Waele relationship, is a type of generalized Newtonian fluid (time-independent non-Newtonian fluid) for which the shear stress, τ, is given by ![]()
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