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Fluids transport properties

The heat transfer coefficient is correlated experimentally with the fluid transport properties (specific heat, viscosity, thermal conductivity and density), fluid velocity and the geometrical relationship between surface and fluid flow. [Pg.346]

The most common means of transporting fluid is the pipeline. Every pipe is a long, cylindrical, completely enclosed conduit used to transport gas, liquid, or both from point to point. Mathematical calculations are used to determine the size of pipe, the fluid transport properties, the flow characteristics, and the energy that must be applied to move... [Pg.212]

In order to calculate / certain dynamic forces of mass flow must first be determined. Knowing these forces resisting flow are along the pipe wall, the work of Osborne Reynolds has shown that certain fluid transport properties compose this friction force. Reynolds proved with... [Pg.217]

Here, Go may be called the multiple source boundary propagator, which describes the water mixture at a location along with the origin/transit times T = (f — f ) of those water masses at the sea surface. It is, by definition, dependent solely on fluid transport properties, and independent of the particular tracer. Since there are no internal sinks or sources of C, we can construct the tracer distribution in a fashion analogous to (46) with... [Pg.3085]

For pressure-based techniques, the lack of an independent equation for the pressure complicates the solution of the momentum equation. Furthermore, the continuity equation does not have a transient term in incompressible flows because the fluid transport properties are constant. The continuity reduces to a kinematic constraint on the velocity held. One possible approach is to construct the pressure field so as to guarantee satisfaction of the continuity equation. In this case, the momentum equation still determines the respective velocity components. A frequently used method to obtain an equation for the pressure is based on combining the two equations. This means that the continuity equation, which does not contain the pressure, is employed to determine the pressure. If we take the divergence of the momentum equation, the continuity equation can be used to simplify the resulting equation. [Pg.1044]

Chung, T. H., Ajlan, M., Lee, L. L. Starling, K. E. 1988. Generalized multiparameter correlation for nonpolar and polar fluid transport-properties. Industrial Engineering Chemistry Research, 27(4), 671-679. [Pg.98]

The basic idea of RANS models is to account for the change in the fluid transport properties by introducing an eddy viscosity, I, also called turbulence viscosity, which relates the Reynolds stress tensor R to the fluid deformation. Such a relationship was first proposed by Boussinesq in the nineteenth century. More formally, this Boussinesq assumption can be written as... [Pg.395]

The general equations of change given in the previous chapter show that the property flux vectors P, q, and s depend on the nonequi-lihrium behavior of the lower-order distribution functions g(r, R, t), f2(r, rf, p, p, t), and fi(r, P, t). These functions are, in turn, obtained from solutions to the reduced Liouville equation (RLE) given in Chap. 3. Unfortunately, this equation is difficult to solve without a significant number of approximations. On the other hand, these approximate solutions have led to the theoretical basis of the so-called phenomenological laws, such as Newton s law of viscosity, Fourier s law of heat conduction, and Boltzmann s entropy generation, and have consequently provided a firm molecular, theoretical basis for such well-known equations as the Navier-Stokes equation in fluid mechanics, Laplace s equation in heat transfer, and the second law of thermodynamics, respectively. Furthermore, theoretical expressions to quantitatively predict fluid transport properties, such as the coefficient of viscosity and thermal... [Pg.139]

Fluid transport properties were not the primary concern at this conference, but progress was also shown here. Remarkable agreement between prediction and experiment for viscosities and thermal conductivities of gaseous mixtures was reported. Clearly, much work needs to be done, especially for liquids. [Pg.436]

It subsequently proved advantageous to develop expressions for universal curves based on experimental results for the correlation of dense fluid transport properties. This is discussed fully in Chapter 10 with respect to xenon, for which accurate diffusion data are available, in addition to viscosity measurements, up to high densities. In the case of diffusion, there is very satisfactory agreement between the exact hard-sphere results and experimental data. [Pg.94]

At the present time, the most successful correlations of dense-fluid transport properties are based upon consideration of the hard-sphere model. One reason for this is that, as discussed in Chapter 5, it is possible to calculate values from theory for this model at densities from the dilute-gas state up to solidification. Second, this is physically a reasonably realistic molecular model because the van der Waals model, which has been successfully applied to equilibrium properties of dense fluids, becomes equivalent to the hard-sphere model for transport properties. [Pg.226]

Dense fluid transport property data are successfully correlated by a scheme which is based on a consideration of smooth hard-sphere transport theory. For monatomic fluids, only one adjustable parameter, the close-packed volume, is required for a simultaneous fit of isothermal self-diffusion, viscosity and thermal conductivity data. This parameter decreases in value smoothly as the temperature is raised, as expected for real fluids. Diffusion and viscosity data for methane, a typical pseudo-spherical molecular fluid, are satisfactorily reproduced with one additional temperamre-independent parameter, the translational-rotational coupling factor, for each property. On the assumption that transport properties for dense nonspherical molecular fluids are also directly proportional to smooth hard-sphere values, self-diffusion, viscosity and thermal conductivity data for unbranched alkanes, aromatic hydrocarbons, alkan-l-ols, certain refrigerants and other simple fluids are very satisfactorily fitted. From the temperature and carbon number dependency of the characteristic volume and the carbon number dependency of the proportionality (roughness) factors, transport properties can be accurately predicted for other members of these homologous series, and for other conditions of temperature and density. Furthermore, by incorporating the modified Tait equation for density into... [Pg.246]

Saline water-bearing formations are broadly distributed across the United States and other parts of the world. The Sleipner project mentioned earlier is one example. Similar projects are under consideration elsewhere in the world. Little attention has been paid to saline aquifers by the energy industry since they have no commercial value. Research efforts are needed to determine the geologic and fluid transport properties of saline water-bearing formations so that their applicability for long-term storage can be determined. [Pg.53]

Dysflie, D.K., Fuchs, A.H., and Rousseau, B. (2000) Fluid transport properties by equilibrium molecular dynamics. 111. Evaluation of united atom interaction potential models for pure alkanes. [Pg.377]

However, according to Freitas et al. (2008), changes in temperature, such as temperature increase, can cause variations in the fluid transport properties, mainly expressed by the solvent viscosity and diffusion coefficient. At the same time, higher temperatures can increase the vapor pressure of the oil. These aspects favor fluid penetration into the pores within the matrix facilitating the extraction by the solvent and oil solubilization. An increase in pressure makes the pores of the matrix suitable for penetration of the solvent facilitating the contact between the solvent and the compoimds to be extracted. [Pg.30]

It is possible to verily this study the relationship between the effect of the temperature increase on the changes in fluid transport properties, such as viscosity and solvent diffusion, in addition to the increase in the vapor pressure of the oil. All of these variables, which underwent changes due to the increase in temperature, facilitate the penetration of fluids into the pores within the vegetable matrix, favoring the removal of the lipid content by the solvent and the resulting solubilization of the oil. [Pg.35]


See other pages where Fluids transport properties is mentioned: [Pg.350]    [Pg.130]    [Pg.212]    [Pg.124]    [Pg.481]    [Pg.70]    [Pg.156]    [Pg.159]    [Pg.306]   
See also in sourсe #XX -- [ Pg.84 ]




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