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arXiv · 1510.08297

Numerical solving unsteady space-fractional problems with the square root of an 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 the square root of an elliptic operator of second order. Finite element approximation in space is employed. To construct approximation in time, regularized two-level schemes are used. The numerical implementation is based on solving the equation with the square root of the elliptic operator using an auxiliary Cauchy problem for a pseudo-parabolic equation. The scheme of the second-order accuracy in time is based on a regularization of the three-level explicit Adams scheme. More general problems for the equation with convective terms are considered, too. The results of numerical experiments are presented for a model two-dimensional problem.

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Petr N. Vabishchevich. 2015-10-28. Numerical solving unsteady space-fractional problems with the square root of an elliptic operator. https://arxiv.org/abs/1510.08297

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