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arXiv · 1708.05351

Local discontinuous Galerkin method for distributed-order time and space-fractional convection-diffusion and Schr\"odinger type equations

Tarek Aboelenen
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Abstract

Fractional partial differential equations with distributed-order fractional derivatives describe some important physical phenomena. In this paper, we propose a local discontinuous Galerkin (LDG) method for the distributed-order time and Riesz space fractional convection-diffusion and Schr\"odinger type equations. We prove stability and optimal order of convergence $O(h^{N+1}+(\Delta t)^{1+\frac{\theta}{2}}+\theta^{2})$ for the distributed-order time and space-fractional diffusion and Schr\"odinger type equations, an order of convergence of $O(h^{N+\frac{1}{2}}+(\Delta t)^{1+\frac{\theta}{2}}+\theta^{2})$ is established for the distributed-order time and Riesz space fractional convection-diffusion equations where $\Delta t$, $h$ and $\theta$ are the step sizes in time, space and distributed-order variables, respectively. Finally, the performed numerical experiments confirm the optimal order of convergence.

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Tarek Aboelenen. 2017-08-16. Local discontinuous Galerkin method for distributed-order time and space-fractional convection-diffusion and Schr\"odinger type equations. https://arxiv.org/abs/1708.05351

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