A moment-based Hermite WENO scheme with unified stencils for hyperbolic conservation laws
Chuan Fan, Jianxian Qiu, Zhuang Zhao
TL;DR
The paper tackles high-order, non-oscillatory solutions for hyperbolic conservation laws by introducing a fifth-order HWENO-U scheme that evolves zeroth- and first-order moments with unified stencils and applies a HWENO limiter during time discretization. A key contribution is the scale-invariant nonlinear weighting based on integral averages $u_{ave}$, which improves robustness across sharp scale variations and ensures identical weights for $u$ and $\zeta u$. The stability analysis via Fourier methods shows that modifying the first-order moment in time discretization is essential for stability, yielding a CFL-like bound of $0<\Delta t/\Delta x\lesssim 0.824$; extensive one- and two-dimensional tests demonstrate fifth-order accuracy, high resolution, and robustness against shocks, outperforming competing HWENO-M and WENO-ZQ schemes in efficiency at similar costs. The approach simplifies implementation with a single reconstruction on unified stencils and is readily extendable to unstructured meshes, broadening applicability to complex flows.
Abstract
In this paper, a fifth-order moment-based Hermite weighted essentially non-oscillatory scheme with unified stencils (termed as HWENO-U) is proposed for hyperbolic conservation laws. The main idea of the HWENO-U scheme is to modify the first-order moment by a HWENO limiter only in the time discretizations using the same information of spatial reconstructions, in which the limiter not only overcomes spurious oscillations well, but also ensures the stability of the fully-discrete scheme. For the HWENO reconstructions, a new scale-invariant nonlinear weight is designed by incorporating only the integral average values of the solution, which keeps all properties of the original one while is more robust for simulating challenging problems with sharp scale variations. Compared with previous HWENO schemes, the advantages of the HWENO-U scheme are: (1) a simpler implemented process involving only a single HWENO reconstruction applied throughout the entire procedures without any modifications for the governing equations; (2) increased efficiency by utilizing the same candidate stencils, reconstructed polynomials, and linear and nonlinear weights in both the HWENO limiter and spatial reconstructions; (3) reduced problem-specific dependencies and improved rationality, as the nonlinear weights are identical for the function $u$ and its non-zero multiple $ζu$. Besides, the proposed scheme retains the advantages of previous HWENO schemes, including compact reconstructed stencils and the utilization of artificial linear weights. Extensive benchmarks are carried out to validate the accuracy, efficiency, resolution, and robustness of the proposed scheme.
