An hp-version of the discontinuous Galerkin time-stepping method for Volterra integral equations with weakly singular kernels

Autor: Lijun Yi, Hongjiong Tian, Lina Wang
Rok vydání: 2021
Předmět:
Zdroj: Applied Numerical Mathematics. 161:218-232
ISSN: 0168-9274
DOI: 10.1016/j.apnum.2020.11.006
Popis: We develop and analyze an hp-version of the discontinuous Galerkin time-stepping method for linear Volterra integral equations with weakly singular kernels. We derive a priori error bound in the L 2 -norm that is fully explicit in the local time steps, the local approximation orders, and the local regularity of the exact solutions. For solutions with singular behavior near t = 0 caused by the weakly singular kernels, we prove optimal algebraic convergence rates for the h-version of the discontinuous Galerkin approximations on graded meshes. Moreover, we show that exponential rates of convergence can be achieved for solutions with start-up singularities by using geometrically refined time steps and linearly increasing approximation orders. Numerical experiments are presented to illustrate the theoretical results.
Databáze: OpenAIRE