Piecewise equidistant meshes for quasilinear turning point problems: Technical report
For researchers solving singularly perturbed boundary value problems with turning points, this provides a robust numerical method with guaranteed accuracy.
The paper develops a finite-difference scheme on piecewise equidistant meshes for quasilinear singularly perturbed turning point problems, achieving second-order accuracy and uniform pointwise convergence in the perturbation parameter, with L1 errors decreasing as the parameter tends to 0.
A class of quasilinear singularly perturbed boundary value problems with a turning point of attractive type is considered. The problems are solved numerically by a finite-difference scheme on a special discretization mesh which is dense near the turning point. The scheme is a combination of the standard central and midpoint schemes and is practically second-order accurate. Pointwise accuracy is uniform in the perturbation parameter and, moreover, L1 errors decrease when the perturbation parameter tends to 0. This is achieved by the use of meshes which generalize the piecewise equidistant Shishkin mesh. Two particular types of meshes are considered and compared.