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arXiv · 2004.11151

Subdiffusion with Time-Dependent Coefficients: Improved Regularity and Second-Order Time Stepping

Bangti Jin·Buyang Li·Zhi Zhou
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Abstract

This article concerns second-order time discretization of subdiffusion equations with time-dependent diffusion coefficients. High-order differentiability and regularity estimates are established for subdiffusion equations with time-dependent coefficients. Using these regularity results and a perturbation argument of freezing the diffusion coefficient, we prove that the convolution quadrature generated by the second-order backward differentiation formula, with proper correction at the first time step, can achieve second-order convergence for both nonsmooth initial data and incompatible source term. Numerical experiments are consistent with the theoretical results.

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Bangti Jin, Buyang Li, Zhi Zhou. 2020-04-23. Subdiffusion with Time-Dependent Coefficients: Improved Regularity and Second-Order Time Stepping. https://arxiv.org/abs/2004.11151

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