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arXiv · 2409.15805

Bound Preserving Lax-Wendroff Flux Reconstruction Method for Special Relativistic Hydrodynamics

Sujoy Basak·Arpit Babbar·Harish Kumar·Praveen Chandrashekar
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Abstract

Lax-Wendroff flux reconstruction (LWFR) schemes have high order of accuracy in both space and time despite having a single internal time step. Here, we design a Jacobian-free LWFR type scheme to solve the special relativistic hydrodynamics equations on Cartesian grids. We then blend the scheme with a first-order finite volume scheme to control the oscillations near discontinuities. We also use a scaling limiter to preserve the physical admissibility of the solution after ensuring the scheme is admissible in means. A particular focus is given to designing a discontinuity indicator model to detect the local non-smoothness in the solution of the highly non-linear relativistic hydrodynamics equations. Finally, we present numerical results for a wide range of test cases to show the robustness and efficiency of the proposed scheme.

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Sujoy Basak, Arpit Babbar, Harish Kumar, Praveen Chandrashekar. 2024-09-24. Bound Preserving Lax-Wendroff Flux Reconstruction Method for Special Relativistic Hydrodynamics. https://arxiv.org/abs/2409.15805

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