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Viscosity coefficient and

The quantity rj in set (9.58) represents the shear viscosity coefficient and depends on the invariant of the anisotropy tensor in the same way as the relaxation time i... [Pg.192]

Equations (9.63)-(9.65) were used, in fact, to evaluate the shear viscosity coefficient and the relaxation times which reveal the nature of dependence on the velocity gradient v 12 or shear stress oyi (Isayev 1973). It is convenient to consider the shear viscosity coefficient and the relaxation time as a generalised function of the first invariant of the tensor of additional stresses... [Pg.193]

Figure 21. Comparison of the temperature coefficient of the B-viscosity coefficient and that of the Walden product for various ions in water (Kay, 1968). Figure 21. Comparison of the temperature coefficient of the B-viscosity coefficient and that of the Walden product for various ions in water (Kay, 1968).
Therefore, switch-off times are independent of the field strength and directly dependent on material parameters, such as viscosity coefficients and elastic constants, and the cell configuration. Therefore, they are often three or four orders of magnitude larger than the switch-on times. However, sophisticated addressing techniques can produce much shorter combined response times ( on + off The nematic director should be inclined, e.g. 1° pretilt,... [Pg.56]

Table VIII.1 shows some of the experimental values that have been obtained for viscosity coefficients and Sutherland constants. It should be... Table VIII.1 shows some of the experimental values that have been obtained for viscosity coefficients and Sutherland constants. It should be...
In Eqs. (43) and (44), H is the channel height in which the meniscus convolutes (or in our case the craze tip opening displacement), % the surface energy of the solid polymer, the equivalent inelastic deformation rate, a non-linear extensional viscosity coefficient, and n a strain rate exponent in the non-linear connection between the equivalent deformation resistance and the equivalent strain rate. The last four quantities are taken to be related by a non-linear constitutive law that is... [Pg.294]

They can be evaluated directly by using the director constraint algorithm to fix the director in the desired direction or one can evaluate the fluctuation relations for the various viscosity coefficients and substituting the values into the above expressions. We finally note that we have not developed any simulation algorithms for Tjy, or K. [Pg.347]

This theory takes into account the micro-rotational effects due to rotation of molecules. This becomes important with polymers or polymeric suspensions. The physical model assigns a substructure to each continuum particle. Each material volume element contains microvolume elements which can translate, rotate, and deform independently of the motion of the microvolime. In the simplest case, these fluids are characterised by 22 viscosity coefficients and the problem is formulated in terms of a system of 19 equations with 19 unknowns. The equations for a 2-D case were solved numerically and compared to experimental results. It is concluded that the model based on the micropolar fluid theory gives a better fit than the Navier - Stokes equations. However, it seems that the difference is small. [Pg.36]

The quantities a, c, f, F, r, and p are the thermal diffusivity, sound speed, heat capacity ratio, bulk viscosity coefficient, shear viscosity coefficient, and density of the sample, respectively and Eo, a, P and Cp are the energy fluence of the laser beam, the optical absorption coefficient, the volume expansion coefficient, and the isobaric heat capacity, respectively, of the fluid. Tlie first and second terms in Eq. 2 describe the time dependences of the thermal and acoustic modes of wave motion, respectively. Since the decays of the acoustic and thermal mode densities back to their ambient values take place on such different time scales (microsecond time scale for acoustic mode and millisecond time scale for thermal mode), they were recorded on the oscilloscope using different time bases. [Pg.96]

The downside is that these base oils have lower values of pressure viscosity coefficients and hence under both hydrodynamic and elastohydrodynamic lubrication conditions, the films formed in contacts will be thinner than that for an iso-viscous, higher sulphur basestock. [Pg.103]

TABLE I. Viscosity Coefficients and their Isobaric and Isochoric Temperature Coefficients for a Number of CommonLiquids at 30° C. and 1 atm. (The viscosity-pressure coefficient data are from... [Pg.138]

Fig. 5.10.8. The temperature variation of the Goldstone mode and soft mode viscosity coefficients, and y, in the smectic C phase of DOBAMBC. (After... Fig. 5.10.8. The temperature variation of the Goldstone mode and soft mode viscosity coefficients, and y, in the smectic C phase of DOBAMBC. (After...
The unusual mole fraction scale for the solution, with 5 x(H+,aq) = -68.2 J mol was used for the calculation of values of Astmc5 for the alkali metal and halide ions as well as Ag+ and CIO4 (Abraham et al. 1982). However, the choices of the value of 5 (H+, aq) and the mole fraction scale caused K+ to appear as a strue-ture making ion. This unacceptable result is corrected by adjustment to the molar scale with 5° (H+, aq) = - 22.2 J mol. Linear correlations of Astmc5 with the viscosity coefficients and with the NMR coefficients (Sect. 3.1.3) and also with the ionic partial molar volumes or their electrostricted volumes were noted by Abraham et al. (1982). [Pg.125]

Here, rji and are viscosity coefficients, and fcg are thermal conductivities of a droplet and a fluid, a is the surface tension, and T is the absolute temperature. A specific variation of the surface temperature 7br(r, 6) of an irradiated particle (Fig. 3) formally results in certain weighted averaging of over the polar angle 6. The exact solution has not been obtained yet, but arguments similar to those used in the case of a solid particle suggest the following form for the final hphth expression for a fluid droplet ... [Pg.1804]

A modified k - e model for determination of turbulent non-newtonian stresses has been used to provide velocity profiles in Poiseuille-Couette flow. Generalized functions are found for the non-newtonian turbulent viscosity coefficients and G > which lead us to formulation of the generalized... [Pg.417]

It pertained to the solvent beyond the first solvation shell, the thickness of which was the molecular diameter of the solvent, d. Linear correlations of - A5 - A5 thus calculated for aqueous solutions of ions with their viscosity coefficients and with the corresponding NMR coefficients were noted by Abraham et al. [21],... [Pg.164]

Thus the model given consists of the convection-diffusion equation for the concentration of the components, relations to determine the density and the viscosity coefficient and hydrodynamic Navier-Stokes equations for incompressible viscous fluid. [Pg.204]


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See also in sourсe #XX -- [ Pg.17 , Pg.18 ]




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