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Stability analysis for

The described method can generate a first-order backward or a first-order forward difference scheme depending whether 0 = 0 or 0 = 1 is used. For 9 = 0.5, the method yields a second order accurate central difference scheme, however, other considerations such as the stability of numerical calculations should be taken into account. Stability analysis for this class of time stepping methods can only be carried out for simple cases where the coefficient matrix in Equation (2.106) is symmetric and positive-definite (i.e. self-adjoint problems Zienkiewicz and Taylor, 1994). Obviously, this will not be the case in most types of engineering flow problems. In practice, therefore, selection of appropriate values of 6 and time increment At is usually based on trial and error. Factors such as the nature of non-linearity of physical parameters and the type of elements used in the spatial discretization usually influence the selection of the values of 0 and At in a problem. [Pg.66]

Stability theory is the central part of the theory of difference schemes. Recent years have seen a great number of papers dedicated to investigating stability of such schemes. Many works are based on applications of spectral methods and include ineffective results given certain restrictions on the structure of difference operators. For schemes with non-self-adjoint operators the spectral theory guides only the choice of necessary stability conditions, but sufficient conditions and a priori estimates are of no less importance. An energy approach connected with the above definitions of the scheme permits one to carry out an exhaustive stability analysis for operators in a prescribed Hilbert space Hh-... [Pg.780]

Bauernschmitt, R., Ahlrichs, R., 1996a, Stability Analysis for Solutions of the Closed Shell Kohn-Sham Equation , J. Chem. Phys., 104, 9047. [Pg.280]

Blumenkrantz, A., and J. Taborek, 1971, Application of Stability Analysis for Design of Natural Circulation Boiling Systems and Comparison with Experimental Data, AlChE Paper 13, Natl. Heat Transfer Conf, Tulsa, OK. (6)... [Pg.523]

Barkey, Tobias and Muller formulated the stability analysis for deposition from well-supported solution in the Tafel regime at constant current [48], They used dilute-solution theory to solve the transport equations in a Nernst diffusion layer of thickness S. The concentration and electrostatic potential are given in this approximation... [Pg.161]

A stability analysis for Chapman-Jfouguet detonations made by Pukhnachev (Ref 6a) to clarify the development of phenomena leading to spinning detonations is discussed under Detonation, Spin (Spinning or Heli-coidal Detonation)... [Pg.569]

J. W. Jerome, Consistency of semiconductor modelling an existence/stability analysis for the stationary van roosbroeck system, SIAM J. Appl. Math., 45 (1985), pp. 565-590. [Pg.158]

The local stability analysis for a two-dimensional system has been given in some detail in chapter 3 and used frequently in later sections. The same general principles apply to any number of variables. Provided the perturbations imposed upon the stationary state are infinitesimal, the growth or decay for an n variable system will be governed by the sum of n exponential terms of the form e 1 1 with i = 1, n. [Pg.355]

Finally, let us briefly point out some essential features of the stability analysis for a more general transport problem. It can be exemplified by the moving a//9 phase boundary in the ternary system of Figure 11-12. Referring to Figure 11-7 and Eqn. (11.10), it was a single independent (vacancy) flux that caused the motion of the boundary. In the case of two or more independent components, we have to formulate the transport equation (Fick s second law) for each component, both in the a- and /9-phase. Each of the fluxes jf couples at the boundary b with jf, i = A,B,... (see, for example, Eqn. (11.2)). Furthermore, in the bulk, the fluxes are also coupled (e.g., by electroneutrality or site conservation). [Pg.281]

The experimental and theoretical literature on instabilities in fiber spinning has been reviewed in detail by Jung and Hyun (28). The theoretical analysis began with the work of Pearson et al. (29-32), who examined the behavior of inelastic fluids under a variety of conditions using linear stability analysis for the governing equations. For Newtonian fluids, they found a critical draw ratio of 20.2. Shear thinning and shear thickening fluids... [Pg.833]

Fig. 14.12 Results of the linearized stability analysis for a White-Metzner-type fluid, indicating the dependence of the critical draw ratio on n and N. [Reprinted by permission from R. J. Fisher and M. M. Denn, A Theory of Isothermal Melt Spinning and Draw Resonance, AIChE J., 22, 236 (1976).]... Fig. 14.12 Results of the linearized stability analysis for a White-Metzner-type fluid, indicating the dependence of the critical draw ratio on n and N. [Reprinted by permission from R. J. Fisher and M. M. Denn, A Theory of Isothermal Melt Spinning and Draw Resonance, AIChE J., 22, 236 (1976).]...
In this section, we will perform the stability analysis for PFPE Zdol and Ztetraol films via the Gibbs free-energy change (AG) for the PFPE system [7] to obtain criteria for uniform, stable thin films. [Pg.28]

About 30(5 from the exciter in the downstream direction the computed disturbance profile matches with the eigen-solution corresponding to the complex wave number value (0.2798261, -0.00728702), with that obtained by the stability analysis for the TS mode. It is interesting to note that there is a local component of the receptivity solution that decays rapidly in either direction. This is called the near-field response or the local solution. Thus, the receptivity solution in this figure consists of the asymptotic solution (away from the exciter) and a local solution. [Pg.82]

Presented solution once again, demonstrates the far-field to correspond to the TS mode obtained by linear stability analysis. For Re = 1000 and LVo = 0.1, the calculated impulse response displays TS wave with ar = 0.279826 and a = —0.007287. The results are shown at a height of y = 1.205(5 - the location of the outer maximum of the eigenvector. Considering the stability properties of the Blasius profile, one expects the flow to be stable for Re = 400 and 4000 - with the latter case showing higher damping than the former, as clearly seen in Fig. 2.21. [Pg.91]

As shown in the previous section for the 2D case with infinite nucleus mass, we also carry out stability analysis for the critical point c and d. The critical points c and d are the equilibrium points of the flow [Eqs. (56)-(58)]. At the same time, they are the equilibrium points of the total flow [Eqs. (47)-(50)]. The stability analysis of the equilibrium points c and d gives that =... [Pg.322]

A stability analysis for such a system was performed by Wicke et al. (98), who modeled the H2/O2 reaction on Pt catalysts. The reaction was simplified to two differential equations that are easily treated analytically ... [Pg.99]

Do the linear stability analysis for all the fixed points for Equation (3.5.7), and confirm that Figure 3.5.6 is correct. [Pg.84]

R. Bauernschmitt, R. Ahlrichs, Stability analysis for solutions of the closed shell Kohn-Sham Equation, /. Chem. Phys. 104 (1996) 9047. [Pg.486]

The stability analysis for closed systems subject to other constraints (i.e., constant T and V or constant T and P) is similar to. and, in fact, somewhat simpler than the analysis here, and so it is left to you (Problem 7.3).]... [Pg.276]

Show that the intrinsic stability analysis for fluid equilibrium at constant temperature and volume leads to the single condition that... [Pg.327]

Although this simple statement is a good rule of thumb for inferring the effects of changes in an equilibrium system, it is not universally valid, and exceptions to it do occur (Problem 13.17). A more general, universally valid statement of this principle is best given within the context of a complete thermodynamic stability analysis for a multicomponent reacting system. For many situations, however, it may be more useful, and even more expeditious, to ascertain the equilibrium shift by direct computation of... [Pg.736]

As we have seen, there may be more than one solution to Eq. [12]. We will consider each steady state solution in turn, that is, we will carry out a local stability analysis for each that satisfies Eq. [12]. Because the local analysis will involve a linearization of the full equations, this type of analysis is also called a linear stability analysis. [Pg.191]

Krey stability analysis for foundations, slopes and retaining walls... [Pg.11]

Janbu, N., Grande, L., and Eggercide, K. (1976), Effective stress stability analysis for gravity structures, Proceedings of the Behavior of Offshore Structure 76, pp. 449-466. [Pg.538]

Although stability analysis for a broad class of fluids can predict draw resonance theoretically, the physical source of the instability is not understood. There are L/D effects as noted by Matsumoto and Bogue [106], which the present theory does not predict. Hagler [91], Chen et al. [92], and later White and Ide [107] argued that draw resonance is a continuous form of ductile failure found in simple elongation of certain melts. Clearly, melts that exhibit ductile failure are also very prone to exhibit draw resonance. But, physically, why do some melts exhibit ductile failure and others do not ... [Pg.172]

Solve the kinetic equation (1.69) for the first Schlogl model. Confirm the results of the linear stability analysis for /r > 0 and /u. < 0. Determine the stability of... [Pg.31]

The stability analysis for parametrically excited systems with delay can be performed by numerical techniques. Such a technique is the semi-discretization method (Insperger and Stepan 2011), which is a time-domain method, or the multi-frequency solution... [Pg.434]

It appears that at least two representative diameters or parameters are required as inputs to produce a realistic/q. It is possible to predict one diameter by using a stability analysis for liquid breakup. However, it appears impossible to predict more than one diameter. This seriously hampers the utility of MEF as a method to predict drop size distributions from first principles. [Pg.489]

Because of the large thermal and concentration gradients, polymerization fronts are highly susceptible to buoyancy-induced convection. Garbey et al. performed the linear stability analysis for the liquid/liquid and liquid/solid cases (29-31). The bifurcation parameter was a frontal Rayleigh number ... [Pg.108]

Shult and Volpert performed the linear stability analysis for the same model and confirmed this result (48), Spade and Volpert studied linear stability for nonadiabatic systems (49), Gross and Volpert performed a nonlinear stability for the one-dimensional case (50), Commissiong et al. extended the nonlinear analysis to two dimensions (this volume). In the former analysis, they confirmed that, unlike in SHS (57), uniform pulsations are difficult to observe in frontal polymerization. In fact, no such one-dimensional pulsating modes have been observed. [Pg.112]

Buckling/stability analysis for individual members and the overall A-Frame configuration. [Pg.441]

Indeed, various early studies employed inviscid K-H stability analysis for predicting the stratified/nonstratified transition boundary in gas-liquid two-phase flow (Kordyban and Ranov [33], Kordyban [34], Wallis and Dobson [35], Taitel and Dukler [19]). However, claiming that for pyp, = Pq Pl Equation 21 has been reduced to (ignoring the contribution of U H / [U (l - H)] in Equa-... [Pg.330]

Sun, J.Z., Tian, X.F., Guan, X.D., et al. 2008. Stability analysis for Loosened Rock Slope of Jinyang Grand Buddha in Taiyan, China. Earth Science Frontiers, 15(4) 227-238 (in Chinese). [Pg.849]


See other pages where Stability analysis for is mentioned: [Pg.559]    [Pg.134]    [Pg.308]    [Pg.333]    [Pg.284]    [Pg.250]    [Pg.226]    [Pg.278]    [Pg.225]    [Pg.192]    [Pg.190]    [Pg.2884]    [Pg.314]   
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