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arXiv · 1805.10782

Numerical method for the time-fractional porous medium equation

Łukasz Płociniczak
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Abstract

This papers deals with a construction and convergence analysis of a finite difference scheme for solving time-fractional porous medium equation. The governing equation exhibits both nonlocal and nonlinear behaviour making the numerical computations challenging. Our strategy is to reduce the problem into a single one-dimensional Volterra integral equation for the self-similar solution and then to apply the discretization. The main difficulty arises due to the non-Lipschitzian behaviour of the equation's nonlinearity. By the analysis of the recurrence relation for the error we are able to prove that there exists a family of finite difference methods that is convergent for a large subset of the parameter space. We illustrate our results with a concrete example of a method based on the midpoint quadrature.

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Łukasz Płociniczak. 2018-05-28. Numerical method for the time-fractional porous medium equation. https://doi.org/10.1137/18m1192561

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