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Three-dimensional numerical method

Two different calculation methods were used for the simulations (1) the generalized Newtonian method as developed above, and (2) the three-dimensional numerical method presented in Section 7.5.1. The generalized Newtonian method used a shear viscosity value that was based on the average barrel rotation shear rate and temperature in the channel. The average shear rate based on barrel rotation (7ft) is provided by Eq. 7.52. Barrel rotation shear rate and the generalized Newtonian method are used by many commercial codes, and that is why it was used for this study. [Pg.282]

To obtain the correction factors, the rotational flow rate must be calculated using the generalized Newtonian method and the three-dimensional numerical method... [Pg.287]

Another reason for the choice of the title is the above-mentioned introduction of the Xa-method and the MS-Xa method by Slater and coworkers. There are, however, in particular two other reasons for choosing the title. The first is the formulation of the Density Functional Theory by Hohenberg and Kohn in 1964 [19], which today is probably one of the most quoted papers in electronic structure calculations. This basic work was followed by another important paper in 1965 by Kohn and Sham [20], where they showed how one could use the method for practical calculations and introduced the Kohn-Sham, KS, exchange potential. Exactly the same expression for the exchange potential had previously been derived by Caspar [21], This exchange potential is therefore often known as the Caspar-Kohn-Sham, GKS, potential. Another very important reason for choice of the title is the introduction of the three dimensional numerical integration method by Ellis and Painter in 1968-1970 [22-24]. This... [Pg.3]

The computation of H and S requires use of efficient accurate three dimensional integration methods, in which the integration is performed numerically as a summation of the function values over a certain point distribution ... [Pg.15]

Having established the accuracy and reliability of the slab-adapted three-dimensional Ewald method, we present in this paragraph numerical results from GCEMC simulations (see Section 5.2.2) for a confined Stockmaycr fluid. The particles then interact with each other via both the long-range. [Pg.320]

A straightforward method bypasses the introduction of the auxiliary exchange-correlation fitting basis and evaluates those matrix elements directly by three dimensional numerical integration. This not only spares a computational step, it also avoids the limitations of the fitting basis set. There still arises a truncation error due to the numerical integration scheme. [Pg.223]

Besides the possibilities of the computation of all molecular properties expressible in terms of density matrices, the ADMA method has other advantages. For example, if electron density computations are compared, then the accuracy of the electron density obtained using the ADMA macromolecular density matrix P((p(A0) corresponds to the ideal MEDLA result that could be obtained using an infinite resolution numerical grid. The memory requirements of the ADMA method is also substantially lower than that of the numerical MEDLA method since it takes much less memory to store density matrices than three-dimensional numerical grids of electron densities, especially if reasonably detailed electron densities are required. [Pg.137]

With reasonable calculation parameters, three-dimensional numerical simulation method has an outstanding performance on checking the reliability of metro construction design, not only in qualitative analysis but also in quantitative computation. [Pg.342]

An extended three-dimensional numerical risk scoring system that includes a method to justify the risk amelioration costs in relation to the amount of risk... [Pg.163]

In at least two industries, extensions have been made to the basic qualitative FMEA method to make it a three-dimensional numerical process. Publications on FMEA by a consortium of automobile manufacturers and by a group of semiconductor equipment manufacturing companies add a detection criterion to the FMEA process. A discussion of their publications follows. [Pg.167]

There have been numerous efforts to inspect specimens by ultrasonic reflectivity (or pulse-echo) measurements. In these inspections ultrasonic reflectivity is often used to observe changes in the acoustical impedance, and from this observation to localize defects in the specimen. However, the term defect is related to any discontinuity within the specimen and, consequently, more information is needed than only ultrasonic reflectivity to define the discontinuity as a defect. This information may be provided by three-dimensional ultrasonic reflection tomography and a priori knowledge about the specimen (e.g., the specimen fabrication process, its design, the intended purpose and the material). A more comprehensive review of defect characterization and related nondestructive evaluation (NDE) methods is provided elsewhere [1]. [Pg.200]

Three basic approaches have been used to solve the equations of motion. For relatively simple configurations, direct solution is possible. For complex configurations, numerical methods can be employed. For many practical situations, particularly three-dimensional or one-of-a-kind configurations, scale modeling is employed and the results are interpreted in terms of dimensionless groups. This section outlines the procedures employed and the limitations of these approaches (see Computer-aided engineering (CAE)). [Pg.100]

When q is zero, Eq. (5-18) reduces to the famihar Laplace equation. The analytical solution of Eq. (10-18) as well as of Laplaces equation is possible for only a few boundary conditions and geometric shapes. Carslaw and Jaeger Conduction of Heat in Solids, Clarendon Press, Oxford, 1959) have presented a large number of analytical solutions of differential equations apphcable to heat-conduction problems. Generally, graphical or numerical finite-difference methods are most frequently used. Other numerical and relaxation methods may be found in the general references in the Introduction. The methods may also be extended to three-dimensional problems. [Pg.556]

Computational methods have played an exceedingly important role in understanding the fundamental aspects of shock compression and in solving complex shock-wave problems. Major advances in the numerical algorithms used for solving dynamic problems, coupled with the tremendous increase in computational capabilities, have made many problems tractable that only a few years ago could not have been solved. It is now possible to perform two-dimensional molecular dynamics simulations with a high degree of accuracy, and three-dimensional problems can also be solved with moderate accuracy. [Pg.359]

Two calculation procedures for steady, three-dimensional flows with recirculation, in Proceedings of the 3rd Int. Conf Numer. Methods Fluid Dyn., Paris (1972). [Pg.252]

Using molecular mechanics calculations to assess the three-dimensional shape of a molecule, various surface properties such as polarity and size can be calculated. The dynamic molecular surface properties can be determined from the (low energy) conformation(s) of the drug molecule obtained by molecular mechanics calculations of conformational preferences. The potential advantage of this method is that the calculated surface character-sitics determine numerous physicochemical properties of the molecules including lipophilicity, the energy of hydration and the hydrogen bond formation capacity [187-... [Pg.824]

Whereas the first applications of the AFDF approach were based on a numerical combination of fuzzy fragment electron densities, each stored numerically as a set density values specified at a family of points in a three-dimensional grid, a more powerful approach is the generation of approximate macromolecular density matrices within the framework of the ADMA method [142-146]. A brief summary of the main steps in the ADMA method is given below. [Pg.70]


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See also in sourсe #XX -- [ Pg.282 ]




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