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Equation developing the

Each simulation example is identified by a file name and title, and each comprises the qualitative physical description with drawing, the model equation development, the nomenclature, the ISIM program, suggested exercises, sample graphical results and literature references. The diskette in the pocket at the back of the book contains the programs and the ISIM software. [Pg.279]

The disappearance of A is given by the complicated Eq. 10, and the formation and disappearance of R is given by an even more complicated equation. Developing the product distribution relationship, solving numerically, and comparing the results with those for plug flow and for mixed flow gives Fig. 15.11 see Johnson (1970) and Levien and Levenspiel (1998). [Pg.348]

By substituting the Mach-number expansions onto the continuity (Eq. 3.238) and thermal-energy (Eq. 3.240) equations, develop the leading-order differential equations. [Pg.148]

The equilibrium constant and equation developed the means to calculate equilibrium. Typically, when the amounts of the reactant or products are given, the equilibrium concentrations can be calculated as long as the equilibrium constant is known at the reaction temperature and the direction of the equations shift (left, toward reactants, or right, toward products) can be predicted. [Pg.123]

It is always risky to identify the origin of an idea. The basic idea of the Big Bang may be identified with the Russian mathematical physicist, Alexander A. Friedmann, who in 1922, armed with Einstein s general relativistic equations, developed the picture of the universe expanding from a point origin. The timing was wrong,... [Pg.212]

Starting with the material balance equation, develop the expression for the impedance response for mass transfer through a stagnant film. [Pg.210]

In understanding the desired and possible chemistry the process at each step should be categorized as to type of reaction and a balanced chemical equation developed. The use of a broad categorization such as given in Table I is frequently used as a starting point. [Pg.10]

In this section, we will consider immiscible radial flows with capillary pressure and prescribed mudcake growth. In particular, we will derive the relevant governing equations, develop the numerical finite difference algorithm and the Fortran implementation, and proceed to demonstrate the computational model in both forward and inverse modes. [Pg.424]

Nearly all reservoirs are water bearing prior to hydrocarbon charge. As hydrocarbons migrate into a trap they displace the water from the reservoir, but not completely. Water remains trapped in small pore throats and pore spaces. In 1942 Arch/ e developed an equation describing the relationship between the electrical conductivity of reservoir rock and the properties of its pore system and pore fluids. [Pg.147]

It was made clear in Chapter II that the surface tension is a definite and accurately measurable property of the interface between two liquid phases. Moreover, its value is very rapidly established in pure substances of ordinary viscosity dynamic methods indicate that a normal surface tension is established within a millisecond and probably sooner [1], In this chapter it is thus appropriate to discuss the thermodynamic basis for surface tension and to develop equations for the surface tension of single- and multiple-component systems. We begin with thermodynamics and structure of single-component interfaces and expand our discussion to solutions in Sections III-4 and III-5. [Pg.48]

In this equation //is the Flamiltonian (developed in the previous section) which consists of the bare system Flamiltonian and a temi coming from the interaction between the system and the light. That is. [Pg.226]

Theories based on the solution to integral equations for the pair correlation fiinctions are now well developed and widely employed in numerical and analytic studies of simple fluids [6]. Furtlier improvements for simple fluids would require better approximations for the bridge fiinctions B(r). It has been suggested that these fiinctions can be scaled to the same fiinctional fomi for different potentials. The extension of integral equation theories to molecular fluids was first accomplished by Chandler and Andersen [30] through the introduction of the site-site direct correlation fiinction c r) between atoms in each molecule and a site-site Omstein-Zemike relation called the reference interaction site... [Pg.480]

The principles of operation of quadnipole mass spectrometers were first described in the late 1950s by Wolfgang Paul who shared the 1989 Nobel Prize in Physics for this development. The equations governing the motion of an ion in a quadnipole field are quite complex and it is not the scope of the present article to provide the reader with a complete treatment. Rather, the basic principles of operation will be described, the reader being referred to several excellent sources for more complete infonnation [13, H and 15]. [Pg.1339]

One writes equations which T and T" are expected to obey. For example, in the early development of these methods [80], the Scln-ddinger equation itself was assumed to be obeyed, so = E V and = E are the two equations (note that, in the IP and EA cases, the latter equation, and the associated Hamiltonian //, refer to one fewer and one more electrons than does the reference equation ft V = E V). [Pg.2188]

More sophisticated approaches to describe double layer interactions have been developed more recently. Using cell models, the full Poisson-Boltzmann equation can be solved for ordered stmctures. The approach by Alexander et al shows how the effective colloidal particle charge saturates when the bare particle charge is increased [4o]. Using integral equation methods, the behaviour of the primitive model has been studied, in which all the interactions between the colloidal macro-ions and the small ions are addressed (see, for instance, [44, 45]). [Pg.2678]

In his classical paper, Renner [7] first explained the physical background of the vibronic coupling in triatomic molecules. He concluded that the splitting of the bending potential curves at small distortions of linearity has to depend on p, being thus mostly pronounced in H electronic state. Renner developed the system of two coupled Schrbdinger equations and solved it for H states in the harmonic approximation by means of the perturbation theory. [Pg.507]

The stochastic differential equation and the second moment of the random force are insufficient to determine which calculus is to be preferred. The two calculus correspond to different physical models [11,12]. It is beyond the scope of the present article to describe the difference in details. We only note that the Ito calculus consider r t) to be a function of the edge of the interval while the Stratonovich calculus takes an average value. Hence, in the Ito calculus using a discrete representation rf t) becomes r] tn) i]n — y n — A i) -I- j At. Developing the determinant of the Jacobian -... [Pg.267]

The equations developed in Chapters 11 and 12 are quite complicated and in many practical applications it may be desirable to replace them by simpler approximate equations. The construction of such approximations, of adequate accuracy, is a field still largely unexplored. Nevertheless, it is important to understand the structure of the complete equations if approximations are to be made deliberately, rather than by inadvertent omission. [Pg.5]

The starting point for developing the model is the set of diffusion equations for a gas mixture in the presence of temperature, pressure and composition gradients, and under the influence of external forces." These take the following form... [Pg.19]

In order to Introduce thermal effects into the theory, the material balance equations developed in this chapter must be supplemented by a further equation representing the condition of enthalpy balance. This matches the extra dependent variable, namely temperature. Care must also be taken to account properly for the temperature dependence of certain parameters In... [Pg.156]

When developing the dusty gas model flux relations in Chapter 3, the thermal diffusion contributions to the flux vectors, defined by equations (3.2), were omitted. The effect of retaining these terms is to augment the final flux relations (5.4) by terms proportional to the temperature gradient. Specifically, equations (5.4) are replaced by the following generalization... [Pg.182]

Components of the governing equations of the process can be decoupled to develop a solution scheme for a three-dimensional problem by combining one- and two-dimensional analyses. [Pg.18]

The standard least-squares approach provides an alternative to the Galerkin method in the development of finite element solution schemes for differential equations. However, it can also be shown to belong to the class of weighted residual techniques (Zienkiewicz and Morgan, 1983). In the least-squares finite element method the sum of the squares of the residuals, generated via the substitution of the unknown functions by finite element approximations, is formed and subsequently minimized to obtain the working equations of the scheme. The procedure can be illustrated by the following example, consider... [Pg.64]

In the decoupled scheme the solution of the constitutive equation is obtained in a separate step from the flow equations. Therefore an iterative cycle is developed in which in each iterative loop the stress fields are computed after the velocity field. The viscous stress R (Equation (3.23)) is calculated by the variational recovery procedure described in Section 1.4. The elastic stress S is then computed using the working equation obtained by application of the Galerkin method to Equation (3.29). The elemental stiffness equation representing the described working equation is shown as Equation (3.32). [Pg.85]

It is evident that application of Green s theorem cannot eliminate second-order derivatives of the shape functions in the set of working equations of the least-sc[uares scheme. Therefore, direct application of these equations should, in general, be in conjunction with C continuous Hermite elements (Petera and Nassehi, 1993 Petera and Pittman, 1994). However, various techniques are available that make the use of elements in these schemes possible. For example, Bell and Surana (1994) developed a method in which the flow model equations are cast into a set of auxiliary first-order differentia] equations. They used this approach to construct a least-sciuares scheme for non-Newtonian flow equations based on equal-order C° continuous, p-version hierarchical elements. [Pg.126]

To develop the scheme we start with the normalization of the governing equations by letting... [Pg.134]

As described in Chapter 3, Section 5.1 the application of the VOF scheme in an Eulerian framework depends on the solution of the continuity equation for the free boundary (Equation (3.69)) with the model equations. The developed algorithm for the solution of the described model equations and updating of the free surface boundaries is as follows ... [Pg.145]

The subject of entropy is introduced here to illustrate treatment of experimental data sets as distinct from continuous theoretical functions like Eq. (1-33). Thermodynamics and physical chemistry texts develop the equation... [Pg.24]

For the reeord, we should point out that the equations developed in this ehapter are extensions of the nonrelativistie, time-independent Schroedinger equation. The Pauli prineiple arises from a relativistie treatment of the problem, but we shall follow the eustom of most ehemists and aeeept it as a postulate, proven beeause it gives the right answers. [Pg.274]


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See also in sourсe #XX -- [ Pg.348 ]




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