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Partial differential equation nonhomogeneous

The Dimensionless Parameter is a mathematical method to solve linear differential equations. It has been used in Electrochemistry in the resolution of Fick s second law differential equation. This method is based on the use of functional series in dimensionless variables—which are related both to the form of the differential equation and to its boundary conditions—to transform a partial differential equation into a series of total differential equations in terms of only one independent dimensionless variable. This method was extensively used by Koutecky and later by other authors [1-9], and has proven to be the most powerful to obtain explicit analytical solutions. In this appendix, this method will be applied to the study of a charge transfer reaction at spherical electrodes when the diffusion coefficients of both species are not equal. In this situation, the use of this procedure will lead us to a series of homogeneous total differential equations depending on the variable, v given in Eq. (A.l). In other more complex cases, this method leads to nonhomogeneous total differential equations (for example, the case of a reversible process in Normal Pulse Polarography at the DME or the solutions of several electrochemical processes in double pulse techniques). In these last situations, explicit analytical solutions have also been obtained, although they will not be treated here for the sake of simplicity. [Pg.581]

Hence, we obtain a semianalytical solution, i.e., the dependent variables at all the node points are obtained as an analytical solution of time t. The procedure for solving linear parabolic partial differential equations with nonhomogeneous boundary conditions can be summarized as follows ... [Pg.365]

By applying the Sturm-Liouville theorem, the coefficient A for partial differential equations with nonhomogeneous boundary conditions is obtained as ... [Pg.625]

In section 7.1.5, non-homogeneity in the boundary conditions was removed by adding w(x) to the solution. However, for partial differential equations with two nonhomogeneous flux boundary conditions, this method does not work. [4] For this case two separate functions (w(x) v(t)) are introduced to take care of the nonhomogeneity of the boundary conditions and the separation of variables method is applied for the partial differential equation with the homogeneous boundary conditions. [Pg.635]

The idea of homogenous spatial distribution of the particles is based on the concept of well-stirred reactor. However, even microscopic reactions produce local nonhomogenities, which can not be always eliminated by diffusion. There are many contraversions about the stochastic formulation of reaction - diffusion systems. Three directions in the theory of random fields seem to be able to cope with such complexity the theory of random measures, the theory of stochastic partial differential equations relating to trajectories, and the theory of Hilbert space valued stochastic processes. The details are beyond of our scope. [Pg.512]

Eq. (6.79) is the Crank-Nicolson implicit formula for the solution of the nonhomogeneous parabolic partial differential equation (6.63). [Pg.401]

Program Description The MATLAB function paraboliclD.m is written for solution of the parabolic partial differential equation in an unsteady-state two-dimensional problem. The boundary conditions are passed to the function in the same format as that of Example 6.1, Initial condition, is a matrix of the values of the dependent variable for all x and y at time / = 0. If the problem at hand is nonhomogeneous, the name of the MATLAB function containing the function/should be given as the 10th input argument. [Pg.413]

This is a nonhomogeneous finite difference equation in two dimensions, representing the propagation of error during the numerical solution of the parabolic partial differential equation (6.18). The solution of this finite difference equation is rather difficult to obtain. For this reason, the von Neumann analysis considers the homogeneous part of Eq. (6.126) ... [Pg.432]


See other pages where Partial differential equation nonhomogeneous is mentioned: [Pg.672]    [Pg.865]    [Pg.866]    [Pg.1956]   
See also in sourсe #XX -- [ Pg.381 , Pg.397 , Pg.400 , Pg.401 , Pg.405 , Pg.413 ]




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