{ "id": "2304.07809", "version": "v1", "published": "2023-04-16T15:24:47.000Z", "updated": "2023-04-16T15:24:47.000Z", "title": "A New Approach for Designing Well-Balanced Schemes for the Shallow Water Equations: A Combination of Conservative and Primitive Formulations", "authors": [ "Remi Abgrall", "Yongle Liu" ], "categories": [ "math.NA", "cs.NA" ], "abstract": "In this paper, we introduce a new approach for constructing robust well-balanced numerical methods for the one-dimensional Saint-Venant system with and without the Manning friction term. Following the idea presented in [R. Abgrall, Commun. Appl. Math. Comput. 5(2023), pp. 370-402], we first combine the conservative and non-conservative (primitive) formulations of the studied conservative hyperbolic system in a natural way. The solution is globally continuous and described by a combination of point values and average values. The point values and average values will then be evolved by two different forms of PDEs: a conservative version of the cell averages and a possibly non-conservative one for the points. We show how to deal with both the conservative and non-conservative forms of PDEs in a well-balanced manner. The developed schemes are capable of exactly preserving both the still-water and moving-water equilibria. Compared with existing well-balanced methods, this new class of scheme is nonlinear-equations-solver-free. This makes the developed schemes less computationally costly and easier to extend to other models. We demonstrate the behavior of the proposed new scheme on several challenging examples.", "revisions": [ { "version": "v1", "updated": "2023-04-16T15:24:47.000Z" } ], "analyses": { "keywords": [ "shallow water equations", "designing well-balanced schemes", "primitive formulations", "robust well-balanced numerical methods", "conservative" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }