TY - JOUR T1 - Numerical Analysis of a Nonlinear Singularly Perturbed Delay Volterra Integro-Differential Equation on an Adaptive Grid AU - Liu , Libin AU - Chen , Yanping AU - Liang , Ying JO - Journal of Computational Mathematics VL - 2 SP - 258 EP - 274 PY - 2022 DA - 2022/01 SN - 40 DO - http://doi.org/10.4208/jcm.2008-m2020-0063 UR - https://global-sci.org/intro/article_detail/jcm/20186.html KW - Delay Volterra integro-differential equation, Singularly perturbed, Error analysis, Monitor function. AB -

In this paper, we study a nonlinear first-order singularly perturbed Volterra integro-differential equation with delay. This equation is discretized by the backward Euler for differential part and the composite numerical quadrature formula for integral part for which both an a priori and an a posteriori error analysis in the maximum norm are derived. Based on the a priori error bound and mesh equidistribution principle, we prove that there exists a mesh gives optimal first order convergence which is robust with respect to the perturbation parameter. The a posteriori error bound is used to choose a suitable monitor function and design a corresponding adaptive grid generation algorithm. Furthermore, we extend our presented adaptive grid algorithm to a class of second-order nonlinear singularly perturbed delay differential equations. Numerical results are provided to demonstrate the effectiveness of our presented monitor function. Meanwhile, it is shown that the standard arc-length monitor function is unsuitable for this type of singularly perturbed delay differential equations with a turning point.