Title
Error Estimates Of A Continuous Galerkin Time Stepping Method For Subdiffusion Problem
Abstract
A continuous Galerkin time stepping method is introduced and analyzed for subdiffusion problem in an abstract setting. The approximate solution will be sought as a continuous piecewise linear function in time t and the test space is based on the discontinuous piecewise constant functions. We prove that the proposed time stepping method has the convergence order O(tau(1+alpha)), alpha is an element of (0, 1) for general sectorial elliptic operators for nonsmooth data by using the Laplace transform method, where tau is the time step size. This convergence order is higher than the convergence orders of the popular convolution quadrature methods (e.g., Lubich's convolution methods) and L-type methods (e.g., L1 method), which have only O(tau) convergence for the nonsmooth data. Numerical examples are given to verify the robustness of the time discretization schemes with respect to data regularity.
Year
DOI
Venue
2021
10.1007/s10915-021-01587-9
JOURNAL OF SCIENTIFIC COMPUTING
Keywords
DocType
Volume
Subdiffusion problem, Continuous Galerkin time stepping method, Laplace transform, Caputo fractional derivative
Journal
88
Issue
ISSN
Citations 
3
0885-7474
0
PageRank 
References 
Authors
0.34
0
4
Name
Order
Citations
PageRank
Yuyuan Yan100.34
Bernard A. Egwu200.34
Zongqi Liang300.34
Yubin Yan400.34