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Laplace formulation calculation

A solution to this heat conduction problem is once again possible applying the Laplace transformation, cf. [2.18], [2.26] or [2.1], p. 317-319, where the part originating from a constant initial temperature was calculated, which fades away to zero after a sufficiently long time interval. As this solution method is fairly complicated we will choose an alternative. It can be expected that the temperature in the interior of the body also undergoes an harmonic oscillation, which with increasing depth x will be damped more and more, and in addition it will show a phase shift. The corresponding formulation for this... [Pg.156]

In the second chapter we consider steady-state and transient heat conduction and mass diffusion in quiescent media. The fundamental differential equations for the calculation of temperature fields are derived here. We show how analytical and numerical methods are used in the solution of practical cases. Alongside the Laplace transformation and the classical method of separating the variables, we have also presented an extensive discussion of finite difference methods which are very important in practice. Many of the results found for heat conduction can be transferred to the analogous process of mass diffusion. The mathematical solution formulations are the same for both fields. [Pg.693]

Equations (210) and (211) constitute the exact solution of our problem formulated in terms of matrix continued fractions. Having determined the Laplace transform Y(co) and noting that CY(lco) = f (i )/fj (0), one may calculate the susceptibility xT( ) from Eq. (201). [Pg.354]

Moments are often used in connection with the different formulations and applications of the general rate model because this model can often be solved algebraically in the Laplace domain and, although this solution cannot be inverted into the spatial domain, the moments of this solution can most often be derived as analytical expressions. However, the use of band moments encounters serious problems both on the calculation and the application fronts. [Pg.311]

For calculations one can use the quantitative values < (A)=/o presented in Table 8.1. However, in the case of d < 4 space, an approximated analytical expression /o can be formulated, using the Laplace method [11]. With this aim we have rewritten (8.32) as a d-multipled Laplace integral... [Pg.290]

Equation 7.151 has a very simple form, but represents a challenging formulation for calculation, since, to find the local current density (and, thus, the electron wind force), one has to solve the Laplace equation for the electric potential in the whole sample at each new time moment (as the void moves and changes the shape). At that, as shown in Figure 7.30a, the ratio of maximum and minimum current densities near the void can reach 2 orders of magnitude. A schematic representation of shape evolution is shown in Figure 7.30b. Since the current... [Pg.247]

The post-HF methods for periodic systems were discussed in Sections 5.2 and 5.3. The incremental technique and the Laplace MP2 approach can be mentioned as the most successful approaches to the correlation in solids [5,192]. The former uses standard molecular codes with clusters of various shapes and sizes to calculate the correlation energy, the latter adopts a formulation of correlation directly in AO basis. [Pg.179]

The example discussed suggests another more realistic formulation of the equilibrium problem. Under the conditions of the previous problem, instead of P, and Pg, we specify the pressure in one phase, say, Pg. The system of Eqs. (8) and (9) is completed by the Laplace equation in the form of Eqs. (23). In the second equation, (23), the dependence /(/ ) is supposed to be known from the geometry of the porous space. The surface tension and the wetting angle are defined as known functions of the thermodynamic conditions (e.g., the surface is assumed to be wet by the condensate and the surface tension is calculated by the parachor method). The volumetric hquid... [Pg.387]


See other pages where Laplace formulation calculation is mentioned: [Pg.53]    [Pg.83]    [Pg.348]    [Pg.372]    [Pg.698]    [Pg.174]    [Pg.177]    [Pg.258]    [Pg.296]    [Pg.402]    [Pg.386]   
See also in sourсe #XX -- [ Pg.430 , Pg.431 ]




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Laplace

Laplace formulation

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