Numerical Treatment

The dynamic model consists of the three differential equations (7.104), (7.110), and (7.120). These define an initial value problem with initial conditions at t = 0. The dynamic, unsteady state of this system is described by these highly nonlinear DEs, while the steady states are defined by nonlinear transcendental equations, obtained by setting all derivatives in the system of differential equations (7.104), (7.110), and (7.120) equal to zero. [Pg.482]

The fluidization conditions of the UNI IT)I process are more complicated due to the change in particle size during the growth of the polymer particles. [Pg.483]

Develop a more sophisticated model that takes this particle growth into account. [Pg.483]

Using the simple model of this section, find the static bifurcation characteristics for a typical industrial UNIPOI unit. [Pg.483]

Compute the basic dynamic characteristics for an industrial UNIPOEr reactor. [Pg.483]

The importance of numerical treatments, however, caimot be overemphasized in this context. Over the decades enonnous progress has been made in the numerical treatment of differential equations of complex gas-phase reactions [8, 70, 71], Complex reaction systems can also be seen in the context of nonlinear and self-organizing reactions, which are separate subjects in this encyclopedia (see chapter A3,14. chapter C3.6). [Pg.793]

For the numerical treatment, the energy exchange processes in a zone, as outlined earlier, are incorporated into a so-called room model. [Pg.1070]

E. Bansch, B. Hdhn. Numerical treatment of the Navier-Stokes equations with slip-boundary condition. Preprint 9-98, Mathematische Fakultat Freiburg. SIAM J Sci Comput (submitted). [Pg.918]

Numerical treatment is necessary. From a measurement of Cb at time t the definite integral in Eq. (3-55) is evaluated, and this gives a value for 2- Emanuel and Knorre show an example of this calculation. Benson - pp treats other examples of the elimination of the time variable. [Pg.81]

Due to the numerous treatment options available, a vari-ety of factors can influence product selection, with patient preference playing a significant role. To improve adherence with therapy, the practitioner should discuss with the patient what options are available and what her preferences are. [Pg.1202]

Gampp, H. Maeder, M. Zuberbiihler, A. D., General non-linear least-squares programfor the numerical treatment of spectrophotometric data on a single-precision game computer, Talanta 27, 1037-1045 (1980). [Pg.257]

The discussion of the GCE of light elements formed by cosmic-ray spallation is based on Pagel (1994) and has a somewhat different outlook from many other treatments in the literature, e.g. Fields, Olive and Schramm (1995), which should be consulted to get another viewpoint. A numerical treatment of the Simple model by Vangioni-Flam et al. (1990) gave similar results to the ones derived more simply here, as did the discussion of inflow models by Prantzos (1994). [Pg.325]

The use of batch reactors in the laboratory is described in Section 2.2.2 for the interpretation of rate of reaction, in Section 3.4.1.1 for experimental methodology, and in Chapter 4 and subsequent chapters for numerical treatment of kinetics experimental... [Pg.294]

Considering the semiclassical description of nonadiabatic dynamics, only the mapping approach [99, 100] and the equivalent formulation that is obtained by requantizing the classical electron analog model of Meyer and Miller [112] appear to be amenable to a numerical treatment via an initial-value representation [114, 116, 117, 121, 122]. Other semiclassical formulations such as Pechukas path-integral formulation [45] and the various connection... [Pg.249]

The fundamentals and numerical treatment ot mixing ot two or more liquid components are described in this section. The simplest fundamental explanation is for two miscible liquid components. For example, the spontaneous mixing of two liquid materials is fundamentally controlled by the free energy of mixing ... [Pg.335]

Bachmann, R., Bruell L., Pallaske, U., and Mrzglod, T., A contribution to the numerical treatment of differential equations arising in chemical engineering, Dechema Monographs 116, 343 (1989). [Pg.252]

Numerical treatment of Eq. (4.104) gives Zmax values for the different composite systems as shown in Table 4.3. It is worth emphasizing that for the SiC fiber-glass matrix composites, z, ax values are very small relative to values, irrespective of the fiber surface treatments and when compared to other epoxy matrix based composites. [Pg.135]

Numerical Treatment of Inverse Problems in Differential and Integral Equations, Eds. P. Deulfhard,... [Pg.192]

From flow visualization and angular velocity measurements, Poe and Acrivos (P12) concluded that the analysis leading to Eqs. (10-37) and (10-38) is valid only for Roq <0.1, while for Re > 6 a sphere rotates unsteadily and the wake is oscillatory. Theoretical or numerical treatments appear to be lacking beyond the near-Stokesian range until much higher Reynolds numbers. [Pg.261]

Reactivity ratios between acrylated lignin model compound (Fig. 2), defined as Mi, with either MM A or S, defined as M2, were determined experimentally in accordance with standard procedures (15). These involve mixing two different vinyl monomers in various molar ratios with catalyst (i.e., benzoyl peroxide) and solvent, heating the mixture to achieve polymerization, and recovering the polymer by the addition of non-solvent, and centrifugation. The respective molar monomer fractions of the copolymer were determined by UV-spectroscopy in the cases where MMA served as M2, and by methoxyl content analysis in those cases in which S was the M2-species. The results were subjected to numerical treatments according to the established relationships of Kelen-Tiidos (17) and Yezrielev-Brokhina-Roskin (YBR) (18), and this is described elsewhere (15). [Pg.520]

Three different structures are found for stellar models with identical luminosity, total mass, core mass, and core radius as the effective temperature is varied. Two of these solutions can correspond to effective temperatures in the range pertinent to SK -69 202. This implies that models for the progenitor of SN 1987A will prove very sensitive to physical assumptions and numerical treatment in structural and evolutionary calculations. [Pg.317]

Equation 16.36 predicts that x(t) oc f1/5 and that the neck growth rate will therefore fall off rapidly with time. The time to produce a neck size that is a given particle-size fraction is a strong function of initial particle size—it increases as R4. Equation 16.36 agrees with the results of a numerical treatment by Nichols and Mullins [11].9... [Pg.395]

Section 2 There are numerous treatments of flatness, a notion introduced for the first time in [523. The most estensive treatments of the material of this section are [SGA13 and [EGA i Vz] See also [Ha23. [Pg.195]

It is well-recognized that the hydrocarbons cyclopropane and cyclobutane have nearly identical strain energies, and so these microcycles have been quite naturally paired in numerous treatments of molecular strain. How similar are cyclobutylamine (12, X = NH2, 13, n = 4, X = NH2) and cyclopropylamine (2, X = NH2,13, n - 3, X = NH2) and other correspondingly monosubstituted cyclobutanes and cyclopropanes18 What about... [Pg.226]

The starting point of a number of theoretical studies of packed catalytic reactors, where an exothermic reaction is carried out, is an analysis of heat and mass transfer in a single porous catalyst since such system is obviously more conductive to reasonable, analytical or numerical treatment. As can be expected the mutual interaction of transport effects and chemical kinetics may give rise to multiple steady states and oscillatory behavior as well. Research on multiplicity in catalysis has been strongly influenced by the classic paper by Weisz and Hicks (5) predicting occurrence of multiple steady states caused by intrapellet heat and mass intrusions alone. The literature abounds with theoretical analysis of various aspects of this phenomenon however, there is a dearth of reported experiments in this area. Later the possiblity of oscillatory activity has been reported (6). [Pg.60]

Numerical Treatment of the Steady-State and Dynamical Cases of the Bubbling Fluidized Bed Catalytic Reactor with Consecutive Reactions... [Pg.184]

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