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Linear conservation law

Some of their properties are simpler than for general networks. For example, the damping oscillations are impossible, i.e. the eigenvalues of kinetic matrix are real (with probability close to one). If constants are not separated, damped oscillations could exist, for example, if all constants of the cycle are equal, ki — k2 — — kyi — k, then (1 + X/kf — 1 and Xm — k(exp(2nitn/n) — 1) m — the case ni — 0 corresponds to the linear conservation law. [Pg.119]

For analysis of kinetic systems, linear conservation laws and positively invariant polyhedra are important. A linear conservation law is a linear function... [Pg.127]

If there is no other independent linear conservation law, then the system is weakly ergodic. The weak ergodicity of the network follows from its topological properties. [Pg.129]

For every monomolecular kinetic system, the Jordan cell for zero eigenvalue of matrix K is diagonal and the maximal number of independent linear conservation laws (i.e. the geometric multiplicity of the zero eigenvalue of the matrix K) is equal to the maximal number of disjoint ergodic components (minimal sinks). [Pg.129]

We construct the attainable region by noting that the concentration space is a vector field with a rate vector (e.g., in Fig. 1, dC /dC/ = RB/R ) defined at each point. Moreover, we are not restricted to concentration space, but can consider any other variable that satisfies a linear conservation law (e.g., mass fractions, residence time, energy, and temperature—for constant heat capacity and density). The attainable region is an especially powerful concept once it is known, performance of the network can often be determined without the network itself. [Pg.251]

In an extreme case, m = n, the system is necessarily open, and there are no linear conservation laws. [Pg.406]

The equation of momentum conservation, along with the linear transport law due to Newton, which relates the dissipative stress tensor to the rate of strain tensor = 1 (y. 4, and which introduces two... [Pg.722]

The kinetic equations describing these four steps have been summarized and discussed in the earlier paper and elsewhere (1,5). They can be combined with conservation laws to yield the following non-linear equations that describe the transient behavior of the reactor. In these equations the units of the state variables T, M, and I are mols/liter, while W is in grams/liter. The quantity A (also mols/liter) represents that portion of the total polymer that is unassociated — i.e. reactive. [Pg.188]

To simulate the particle-particle collision, the hard-sphere model, which is based on the conservation law for linear momentum and angular momentum, is used. Two empirical parameters, a restitution coefficient of 0.9 and a friction coefficient of 0.3, are utilized in the simulation. In this study, collisions between spherical particles are assumed to be binary and quasi-instantaneous. The equations, which follow those of molecular dynamic simulation, are used to locate the minimum flight time of particles before any collision. Compared with the soft-sphere particle-particle collision model, the hard-sphere model accounts for the rotational particle motion in the collision dynamics calculation thus, only the translational motion equation is required to describe the fluid induced particle motion. In addition, the hard-sphere model also permits larger time steps in the calculation therefore, the simulation of a sequence of collisions can be more computationally effective. The details of this approach can be found in the literature (Hoomans et al., 1996 Crowe et al., 1998). [Pg.16]

The behavior of a reactive wave depen ds on the flow of its reacting and product-gases. The conservation laws lead to systems of partial differential equations of the first order which are quasilinear, ie, equations in which partial derivatives appear linearly. In practical cases special symmetry of boundary and initial conditions is often invoked to reduce the number of independent variables. [Pg.700]

All conservation laws together define a linear subspace of lattice points in the total state space. The accessible subspace lies in this subspace and usually is identical with it, but not necessarily so. A counterexample would be... [Pg.169]

Here vT is the transposed matrix of the Horiuti numbers (stoichiometric numbers) and Tint the matrix of the intermediate stoichiometric coefficients. The size for the matrices vT and rint is (P x S) and (S x Jtot), respectively, where S is the number of steps, Jtot the total number of independent intermediates, and P the number of routes. Due to the existence of a conservation law (at least one), the catalyst quantity and the number of linearly independent intermediates will be... [Pg.191]

Since As is not a total concentration of electron acceptors c but a neutral fraction of them, the relationship between As and c [4] I A ], as well as the T) 1 (c) dependence, are complex and non-linear at large 7o- In this sense the original Stem-Volmer law breaks down with an increase in light intensity as well as with a decrease in the total quencher concentration c. In both cases one has to find first the As(c) dependence before using it in Eqs. (3.511). As follows from Eq. (3.509b) and the conservation law for acceptors (Nj c 4V), this dependence is given by the following relationship ... [Pg.293]

First, we need to identify the state variables y describing the chemical equilibrium. Following the notation of Gorban and Karlin (2003), the conservation laws in chemical reactions introduce k linearly independent vectors blr b2,..., bk. The state variables describing the system at the chemical equilibrium are... [Pg.90]

For each continuous phase k present in a multiphase system consisting of N phases, in principle the set of conservation equations formulated in the previous section can be applied. If one or more of the N phases consists of solid particles, the Newtonian conservation laws for linear and angular momentum should be used instead. The resulting formulation of a multiphase system will be termed the local instant formulation. Through the specification of the proper initial and boundary conditions and appropriate constitutive laws for the viscous stress tensor, the hydrodynamics of a multiphase system can in principle be obtained from the solution of the governing equations. [Pg.242]

Assuming that this is the only conservation law for this system, then there exist no linear dependencies. Only 771 and the thermostat center r/c = however, are independently coupled to the dynamics. All other combinations of the thermostat variables k > 2 are trivial. As such, the phase space compressibility of the system can be written as... [Pg.161]

In 1959, Godunov [64] introduced a novel finite volume approach to compute approximate solutions to the Euler equations of gas d3mamics that applies quite generally to compute shock wave solutions to non-linear systems of hyperbolic conservation laws. In the method of Godunov, the numerical approximation is viewed as a piecewise constant function, with a constant value on each finite volume grid cell at each time step and the time evolution... [Pg.1031]

The application of QBMM to Eq. (C.l) will require a closure when m(7 depends on 7 Nevertheless, the resulting moment equations (used for the QMOM or the EQMOM) and transport equations for the weights and abscissas (used for the DQMOM) will still be hyperbolic. In terms of hyperbolic conservation laws, the moments are conserved variables (which result from a linear operation on /), while the weights and abscissas are primitive variables. Because conservation of moments is important to the stability of the moment-inversion algorithms, it is imperative that the numerical algorithm guarantee conservation. For hyperbolic systems, this is most easily accomplished using finite-volume methods (FVM) (or, more specifically, realizable FVM). The other important consideration is the accuracy of the moment closure used to close the function, as will be described below. [Pg.447]

The phase information is transmitted from the quantum source (atom) to photons via the conservation laws. In fact, only three physical quantities are conserved in the process of radiation energy, linear momentum, and angular momentum [26]. All of them are represented by the bilinear forms in the photon operators. [Pg.445]

A complete mathematical description of the evolution of a physical quantity in a macroscopic continuous system usually arises from the combination of fundamental conservation laws, like conservation of mass and linear momentum. For a systematic study of systems of conservation laws see Majda (1984). A conservation law states the physical balance between the local variation of the density of a physical quantity (p(r,r) within a given region Q e 9 3 of the space and the flux of this quantity across the external boundary dQ eQ. This law may be written as... [Pg.153]

The usual procedures for the conception of electrochemical reactors arise from the mass conservation laws and the hydrodynamic structure of the device. In fact, four types of balances can be considered energy, charge, mass, and linear movement quantity. Since the reactor must include the anodic and the cathodic reactions, it is possible to make a complete balance for the mass. The temperature also governs the stability of a chemical reactor, but in the case of an electrochemical device, the charge involved in the entire process has to be considered first [3-5]. [Pg.319]


See other pages where Linear conservation law is mentioned: [Pg.128]    [Pg.129]    [Pg.349]    [Pg.128]    [Pg.129]    [Pg.349]    [Pg.721]    [Pg.721]    [Pg.721]    [Pg.722]    [Pg.96]    [Pg.104]    [Pg.23]    [Pg.248]    [Pg.85]    [Pg.200]    [Pg.428]    [Pg.18]    [Pg.257]    [Pg.136]    [Pg.291]    [Pg.291]    [Pg.368]    [Pg.23]    [Pg.41]    [Pg.257]    [Pg.71]    [Pg.1032]    [Pg.318]    [Pg.154]   
See also in sourсe #XX -- [ Pg.127 ]




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