TY - JOUR T1 - Orthogonal Spline Collocation for Singularly Perturbed Reaction Diffusion Problems in One Dimension AU - Mishra , Pankaj AU - Sharma , Kapil K. AU - Pani , Amiya K. AU - Fairweather , Graeme JO - International Journal of Numerical Analysis and Modeling VL - 4 SP - 647 EP - 667 PY - 2019 DA - 2019/02 SN - 16 DO - http://doi.org/ UR - https://global-sci.org/intro/article_detail/ijnam/13019.html KW - Singularly perturbed reaction diffusion problems, orthogonal spline collocation, Shishkin mesh, quasi-optimal global error estimates, superconvergence. AB -

An orthogonal spline collocation method (OSCM) with $C^1$ splines of degree $r$ ≥ 3 is analyzed for the numerical solution of singularly perturbed reaction diffusion problems in one dimension. The method is applied on a Shishkin mesh and quasi-optimal error estimates in weighted $H$$m$ norms for $m$ = 1, 2 and in a discrete $L$2-norm are derived. These estimates are valid uniformly with respect to the perturbation parameter. The results of numerical experiments are presented for $C$1 cubic splines ($r$ = 3) and $C$1 quintic splines ($r$ = 5) to demonstrate the efficacy of the OSCM and confirm our theoretical findings. Further, quasi-optimal a $priori$ estimates in $L$2, $L$ and $W$1,∞-norms are observed in numerical computations. Finally, superconvergence of order 2$r$ − 2 at the mesh points is observed in the approximate solution and also in its first derivative when $r$ = 5.