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Z model

The experimental data are predicted well by the ASM and RSM models but the k-Z model fails to account for most of the curvature effects. [Pg.105]

Validation and Application. VaUdated CFD examples are emerging (30) as are examples of limitations and misappHcations (31). ReaUsm depends on the adequacy of the physical and chemical representations, the scale of resolution for the appHcation, numerical accuracy of the solution algorithms, and skills appHed in execution. Data are available on performance characteristics of industrial furnaces and gas turbines systems operating with turbulent diffusion flames have been studied for simple two-dimensional geometries and selected conditions (32). Turbulent diffusion flames are produced when fuel and air are injected separately into the reactor. Second-order and infinitely fast reactions coupled with mixing have been analyzed with the k—Z model to describe the macromixing process. [Pg.513]

The model of the ciystallizei and selective removal devices that led to equations 64—66 is referred to as the R-Z crystallizer. It is an obvious idealization of actual crystallizers because of the perfect cuts assumed at and However, it is a useful approximation to many systems and it allows quahtative analyses of complex operations. The R-Z model may also be representative of inadvertant classification, ie, fines or course crystals may be preferentially removed from a crystallizer without installation of specific hardware to accomphsh such an objective. [Pg.354]

Fig. 2 also compares the relative N/C enrichments for an initial 40 Mq star. For high mass stars (> 30 Mq), higher Z models have the larger enrichments, i.e. a situation opposite to that described above. The reason is that mass loss effects dominate over mixing. Higher Z stars have a higher mass loss, which... [Pg.310]

This implementation is second-order accurate with respect to the time and the size step. The scheme is general applicable and as shown in the next section, this scheme is also sensitive for discontinuities in Gn as caused by the R-Z model for fines removal. The oscillations are however less severe than for the method of lines. Also for this method a first-order scheme was Implemented. Here the so-called Lax scheme wcus chosen (8) ... [Pg.164]

Yablonskii, G. S., Spivak, S. 1., and Lazman, M. Z., Modeling of complex catalytic reactions, in "Proceedings of the 4th International Symposium on Systems Analysis and Simulation (Berlin, Germany)" (A. Sydow Ed.), pp. 651-656. Elsevier, New York. (1992). [Pg.90]

Cao, Z., Modeling of Gas Hydrates from First Principles, Ph.D. Thesis, Massachusetts Institute of Technology (2002). [Pg.314]

Groves, J.T. and Han, Y.Z., Models and Mechanisms of Cytochrome P450 Action, in Cytochrome P450 Structure, Mechanism, and Biochemistry, Second Edition. P.R. Ortiz de Montellano, Editor. 1995, Plenum Press New York and London, p. 3-48. [Pg.243]

The existence of the LVRPA in the reaction rate expression (Equation 75) makes necessary the solution of the RTE in the pilot scale reactor. As explained before, the lamps length is significantly larger than the reactor width Yr, thus imiformity of radiation is considered along the y direction. Therefore, a two-dimensional (x, z) model for the spatial variations of the radiation field was adopted. The angular distribution of radiation was modeled with the spherical coordinates 6, (j>). The RTE for a two-dimensional, two-directional model is (Brandi et al., 1996, 1999),... [Pg.279]

The difference Fourier map calculated from this equation should be near zero in value and featureless where the model corresponds to the correct structure, as the two electron densities would essentially subtract to zero (assuming F0bs and Fcaic are scaled properly to one another). Where they differ, however, is where we would expect features to appear. At those places where the model contains atoms, and therefore electron density, but the true structure does not, then p(x, y, z)expt —p(x, y, z)modei will be negative. Negative density will appear at that location in the difference Fourier map. If the model lacks atoms, hence electron density, at places occupied by atoms in the true structure, the p(x, y, z)eXpt -p(x, y, z,)model will produce positive density. [Pg.225]

Adamcikova and Treindl (1976) recorded the time dependence of the limiting diffusion current of the Mn(II)/Mn(III) catalyst ions by a polarograph with a rotating platinum electrode. The results of the kinetic measurements were also discussed by referring to the B-Z model, [See G G],... [Pg.84]

Starting with the B-Z model, Fujisaka and Yamada (1980) studied the horatian behavior of coupled B-Z systems. [Pg.91]

In the Lotka-Volterra model (3.68)-(3.69), f(P) = P. Model (3.71)-(3.72) is by no means the only possibility. Another popular choice is to assume that the functional response / depends not only on the prey, but it is ratio-dependent, i.e. it depends on the a mount of prey per predator f = f(P/Z), modelling competition for food among predators, that is absent in the previous models. An example is ... [Pg.113]

The constant force on each electron is positive, and the infinite potential barrier (needed to normalize the orbitals) is far away L oo. The chemical potential is fi = 0. Classically, electrons are confined to the half space z > 0, but in our quantum treatment they tunnel into the classically forbidden region z < 0. The linear variation of the effective potential in the region close to z = 0 can model the Kohn-Sham potential in the surface or edge region of jellium [23], and the evanescent decay of the electron density for large negative z models the tail of the electron density (which is not in principle described by any gradient expansion). [Pg.299]

Tkble 2.8 Coefficients of the initial VARX(Z) model for de-alkylation plant... [Pg.46]

Figure 2.17 Scatterplot of residuals for outlier corrected VARX Z) model of the dealkylation plant... Figure 2.17 Scatterplot of residuals for outlier corrected VARX Z) model of the dealkylation plant...
Table A.4 ANOVA table for tfie initial VARX Z) model witfi outlier correction and variable selection... Table A.4 ANOVA table for tfie initial VARX Z) model witfi outlier correction and variable selection...
Nissan reduced the weight of the front panel of its low-production Fairlady Z model by 30% by replacing a standard class A SMC with a lightweight grade density of 1.3, against 1.85 g/cm, with no increase... [Pg.516]

Holcman, D., Schuss, Z. Modeling calcium dynamics in dendritic spines. SIAM J. Appl. Math. 65(3), 1006-1026(2005). http //link.aip.Org/link/7SMM/65/1006/l... [Pg.433]

Figure 9.11a shows schematically a mixed suspension crystallizer being operated with FD and CPR the R-Z model of Randolph and Larson (1988). Figure 9.11b shows an idealized population density plot for the crystals suspended within the crystallizer. The CSDs in the three size ranges divided by the cut-sizes Lf and may be expressed by... [Pg.422]

Figure 9.11. Mixed suspension crystallizer operating with fines destruction and classified product removal a) the R-Z model, b) population density plot... Figure 9.11. Mixed suspension crystallizer operating with fines destruction and classified product removal a) the R-Z model, b) population density plot...
Ansar M, Xinwei W, Chouwei Z. Modeling strategies of 3D woven composites a review. Compos Struct 2011 93 1947-63. [Pg.26]


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See also in sourсe #XX -- [ Pg.195 ]




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