Using the Sharp scheme of higher-order accuracy for solving some nonlinear hyperbolic systems of equations

Разностная схема Диез повышенного порядка точности, ранее разработанная для решения скалярного одномерного уравнения переноса, с помощью балансно-характеристического подхода распространена на нелинейные системы уравнений мелкой воды и уравнений Эйлера. Для обеих систем уравнений решены тестовые задачи, иллюстрирующие особенности решений, полученных с помощью описываемой разностной схемы. The Sharp difference scheme of higher-order accuracy developed previously for solving the scalar one-dimensional transport equation is extended to the shallow water nonlinear systems and to the systems of Euler equations using the balance-characteristic approach. For these systems, a number of test problems are solved to illustrate the features of the solutions obtained by the described difference scheme.

Schemes with Well-Controlled Dissipation. Hyperbolic Systems in Nonconservative Form

We propose here a class of numerical schemes for the approximation of weak solutions to nonlinear hyperbolic systems in nonconservative form—the notion of solution being understood in the sense of Dal Maso, LeFloch, and Murat (DLM). The proposed numerical method falls within LeFloch-Mishra's framework of schemes with well-controlled dissipation (WCD), recently introduced for dealing with small-scale dependent shocks. We design WCD schemes which are consistent with a given nonconservative system at arbitrarily high-order and then analyze their linear stability. We then investigate several nonconservative hyperbolic models arising in complex fluid dynamics, and we numerically demonstrate the convergence of our schemes toward physically meaningful weak solutions.