TY - JOUR T1 - A New Finite Difference Well-Balanced Mapped Unequal-Sized WENO Scheme for Solving Shallow Water Equations AU - Li , Liang AU - Wang , Zhenming AU - Zhu , Jun JO - Advances in Applied Mathematics and Mechanics VL - 5 SP - 1176 EP - 1193 PY - 2024 DA - 2024/07 SN - 16 DO - http://doi.org/10.4208/aamm.OA-2022-0228 UR - https://global-sci.org/intro/article_detail/aamm/23290.html KW - Shallow water equations, exact C-property, mapping function, well-balanced unequalsized WENO (WBMUS-WENO) scheme. AB -

In this paper, we propose a newly designed fifth-order finite difference well-balanced mapped unequal-sized weighted essentially non-oscillatory (WBMUS-WENO) scheme for simulating the shallow water systems on multi-dimensional structured meshes. We design new non-linear weights and a new mapping function, so that the WBMUS-WENO scheme can maintain fifth-order accuracy with a small $ε$ even nearby the extreme points in smooth regions. The truncation errors of the scheme is smaller and it has better convergence in simulating some steady-state problems. Unlike the traditional well-balanced WENO-XS scheme [29], this new WBMUS-WENO scheme uses three unequal-sized stencils, denotes the linear weights to be any positive numbers on condition that their summation is one. By incorporating a quartic polynomial on the whole big stencil into WENO reconstruction, the WBMUS-WENO scheme is simple and efficient. Extensive examples are performed to testify the exact C-property, absolute convergence property, and good representations of this new WBMUS-WENO scheme.