Multigroup diffusion equations time-dependent

We shall concentrate on surveying the available numerical methods for solving the multi-dimensional multigroup diffusion equations. Since Dr. Ehrlich has already sketched the numerical methods available for treating the case of one space variable, we shall therefore concentrate on the cases of several space variables, although in general our theoretical discussions will be phrased independently of the number of space variables. In all cases we shall attempt to discuss both the rigorous mathematical features and the practical applications of these various numerical methods to both the time independent and time dependent diffusion equations. 

Iterative methods for time dependent multigroup diffusion equations. 

The numerical solution of time dependent multigroup diffusion equations has not yet received as much attention as the number of numerical techniques, which are presently available for such problems, would suggest. We now consider the time dependent multigroup diffusion equations with an external source... 

R. S. Varga and M. A. Martino, The theory for the numerical solution of time-dependent and time-independent multigroup diffusion equations. Proceedings of the Second International Conference on the Peaceful Uses of Atomic Energy, Geneva, 1958, vol. 16, pp. 570-577. 

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