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arXiv · 2405.07620

New Low-Dissipation Central-Upwind Schemes. Part II

Shaoshuai Chu·Alexander Kurganov·Ruixiao Xin
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Abstract

The low-dissipation central-upwind (LDCU) schemes have been recently introduced in [A. Kurganov and R. Xin, J. Sci. Comput., 96 (2023), Paper No. 56] as a modification of the central-upwind (CU) schemes from [{\sc A. Kurganov and C. T. Lin, Commun. Comput. Phys., 2 (2007), pp. 141-163}]. The LDCU schemes achieve much higher resolution of contact waves and many (two-dimensional) structures resulting from complicated wave interaction. However, the LDCU schemes sometimes produce more oscillatory results compared with the CU schemes, especially near the computational domain boundaries. In this paper, we propose a very simple -- yet systematic -- modification of the LDCU schemes, which completely eliminates the aforementioned oscillations almost without affecting the quality of the computed solution.

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Shaoshuai Chu, Alexander Kurganov, Ruixiao Xin. 2024-05-13. New Low-Dissipation Central-Upwind Schemes. Part II. https://arxiv.org/abs/2405.07620

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