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arXiv · 1704.03851

Numerical solution of time-dependent problems with fractional power elliptic operator

Petr N. Vabishchevich
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Abstract

An unsteady problem is considered for a space-fractional equation in a bounded domain. A first-order evolutionary equation involves a fractional power of an elliptic operator of second order. Finite element approximation in space is employed. To construct approximation in time, standard two-level schemes are used. The approximate solution at a new time-level is obtained as a solution of a discrete problem with the fractional power of the elliptic operator. A Pade-type approximation is constructed on the basis of special quadrature formulas for an integral representation of the fractional power elliptic operator using explicit schemes. A similar approach is applied in the numerical implementation of implicit schemes. The results of numerical experiments are presented for a test two-dimensional problem.

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Petr N. Vabishchevich. 2017-04-12. Numerical solution of time-dependent problems with fractional power elliptic operator. https://doi.org/10.1134/s0965542518030120

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