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Numerical modeling correlations

The correlations derived from the analytical models, numerical modeling, and experimental results are listed in Table 4.21. The dimensionless numbers used to describe the droplet deformation... [Pg.303]

There have been books on droplet-related processes. However, the present book is probably the first one that encompasses the fundamental phenomena, principles and processes of discrete droplets of both normal liquids and melts. The author has attempted to correlate many diverse mechanisms and effects in a single and common framework in an effort to provide the reader with a new perspective of the identical basic physics and the inherent relationship between normal liquid and melt droplet processes. Another distinct and unique feature of this book is the comprehensive review of the empirical correlations, analytical and numerical models and computer simulations of droplet processes. These not only provide practical and handy approaches for engineering calculations, analyses and designs, but also form a useful basis for future in-depth research. Therefore, the present book covers the fundamental aspects of engineering applications and scientific research in the area. [Pg.534]

Numerous model calculations correlating aqueous VPIE s using simple harmonic or pseudo-harmonic cell models have been reported (see Fig. 5.8 and Table 5.8 for an ultra-simple version). Such calculations show the importance of the librational hydrogen bonded modes and the stretch-libration interaction in determining VPIE for D or T substitution. [Pg.170]

Solutions for this type of kinetics can only be achieved numerically. Model calculations with constant kinetic parameters have been made [H. Wiedersich, et al. (1979)], however, the modeling of realistic transport (diffusion) coefficients which enter into the flux equations is most difficult since the jump rate vA vB. Also, the individual point defects have limited lifetimes which determine the magnitude of correlation factors (see Section 5.2.2). Explicit modeling for dilute or non-dilute alloys can be found in [A.R. Allnatt, A.B. Lidiard (1993)]. [Pg.320]

Here, CA and CB (upper case) denote the mean molar concentrations of reactants A and B while CA and CB (lower case) denote the local concentration fluctuations that result from turbulence. When the species are perfectly mixed, the second term on the right side containing the correlation of the concentration fluctuations, will approach zero. Otherwise, if the species are not perfectly mixed, this term will be negative and will reduce the reaction rate. Estimating this correlation term is not straightforward and numerous models are available. An excellent discussion on this subject was given by Hannon [1],... [Pg.796]

In this section, the correlation in the heat flux ratio versus the pyrolyzed depth given by Equation 19.14 is incorporated into the numerical model to predict the pyrolysis process of the PA6 nanocomposite at different heat fluxes and thicknesses. The boundary conditions remain as those given by Equations 19.8 and 19.9. However, the MLR is now calculated from the heat flux ratio correlation in Equation 19.14 as... [Pg.540]

The error model used in the minimization is based on the hypothesis that the residuals have zero mean and are normally distributed. The first is easily checked, the latter is only possible when sufficient data points are available and a distribution histogram can be constructed. An adequate model also follows the experimental data well, so if the residuals are plotted as a function of the dependent or independent variable(s) a random distribution around zero should be observed. Nonrandom trends in the residuals mean that systematic deviations exist and indicate that the model is not completely able to follow the course of the experimental data, as a good model should do. This residual trending can also be evaluated numerically be correlation calculations, but visual inspection is much more powerful. An example is given in Fig. 12 for the initial rate data of the metathesis of propene into ethene and 2-butenc [60], One expression was based on a dual-site Langmuir-Hinshelwood model, whereas the other... [Pg.318]

The results obtained from the numerical model were found to be in agreement with the experimental data. A semiempirical correlation between the distribution coefficient and the equilibrium external phase metal ion concentration was developed for use in the modeling. [Pg.714]

So far boundary conditions for gas phase calculations are taken from measurements or empirical correlation, limiting the application only to specific cases. Therefore the aim of the current project is to develop a numerical model, which predicts the conversion of the solid fuel in the packed bed. The model should take different operating parametors and main fuel properties, such as size and humidity of the fuel particles, into account. [Pg.586]

The past 5 years have seen considerable progress in the development of whole-earth mantle convection models that show excellent correlations with subduction and mid-ocean ridge patterns, allowing us to begin to model the interactions between asthenospheric flow and the heterogeneous plates moving in response to this flow. Doin et al. (1997) examined controls of asthenospheric flow on plate thickness, and considered thick cratonic roots. Their 3D simulations indicate that cratonic roots are stable only if the root is buoyant and more viscous than normal continental lithosphere. Sleep (1994, 1997) has used these 3D models to parameterize a numerical model of plume-lithosphere interactions... [Pg.137]

Over recent years, a great deal of numerical modeling work has been carried out using computational fluid dynamics to derive particle charging models " however, the basic models need experimental support because the equations cannot be analytically solved. A reasonable alternative to modeling is proposed by Cochet, " who developed an equation, which appears to give reasonable correlation to actual precipitator measurements in the critical size range, as tested and reported by Hewitt. [Pg.853]

For the relative (slip) velocity numerous empirical correlations are available in the literature [34]. Hence it follows that each component of the dispersed phase momentum equation is reduced to an algebraic-slip relation (3.428). This is the reason why this mixture model formulation is referred to as the algebraic-slip mixture model. [Pg.468]

The end results of a fit of the parameters in Heff to a set of spectroscopic data are (1) a set of molecular constants, standard errors, and correlation coefficients for the constants (2) a quality of fit indicator (cr) (3) a numerical model capable of reproducing the fitted data set without systematic error larger than the measurement precision and (4) a model capable of both extrapolating to unobserved levels and computing properties other than eigenenergies from the eigenvectors of Heff. [Pg.255]

Multiple realizations of conductivities at the small scale of 5 m by 5 m cells are generated. For each realization, the numerical modelling described in the previous subsection is applied. The realizations are generated independently for each formation type and for the vertical fracture in each formation type by sequential simulation using the code gcosmSd (Gomez-Hemandez, 1991). For each formation the same spatial correlation (10 m range... [Pg.245]

Results from these analyses are also presented in Table 1. It can be seen that including an EDZ in the analysis increased the total seepage into the buffer-filled portions of the borehole (SR3 and SR4). The numerical results correlated more closely to the pre-placement experimental results than the results produced without an EDZ, particularly for zones SR3 and SR4. The experimentally measured results for zone SR2 were very low for the pre-placement stage. However a good match was found between the decommissioning seepage for zone SR2 and the numerically modelled results. [Pg.468]

In order to obtain a correlation, the outflow of the effervescent spray was simulated by a numerical model based on the Navier-Stokes equations and the particle tracking method. The external gas flow was considered turbulent. In droplet phase modeling, Lagrangian approach was followed. Droplet primary and secondary breakup were considered in their model. Secondary breakup consisted of cascade atomization, droplet collision, and coalescence. The droplet mean diameter under different operating conditions and liquid properties were calculated for the spray SMD using the curve fitting technique [43] ... [Pg.518]


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