In this paper, we propose a novel approximation strategy for time-dependent hyperbolic systems of conservation laws for the Euler system of gas dynamics that aims to represent the dynamics of strong interacting discontinuities. The goal of our method is to allow an approximation with a high-order of accuracy in smooth regions of the flow, while ensuring robustness and a non-oscillatory behaviour in the regions of steep gradients, in particular across shocks. Following the Multidimensional Optimal Order Detection (MOOD) (Clain et al., Journal of Computational Physics 2011; Diot et al., Computer & Fluids 2012) approach, a candidate solution is computed at a next time level via a high-order accurate explicit scheme (Abgrall, Journal of Scientific Computing 2017; Abgrall et al., Computers & Mathematics with Applications 2018). A so-called detector determines if the candidate solution reveals any spurious oscillations or numerical issue and, if so, only the troubled cells are locally recomputed via a more dissipative scheme. This allows to design a family of "a posteriori" limited, robust and positivity preserving, as well as high accurate, non-oscillatory and effective scheme. Among the detecting criteria of the novel MOOD strategy, two different approaches from literature, based on the work of Clain et al. (Journal of Computational Physics 2011), Diot et al. (Computer & Fluids 2012) and of Vilar (Journal of Computational Physics 2019), are investigated. Numerical examples in 1D and 2D, on structured and unstructured meshes, are proposed to assess the effective order of accuracy for smooth flows, the non-oscillatory behaviour on shocked flows, the robustness and positivity preservation on more extreme flows.
翻译:在本文中,我们为气体动态Euler系统基于时间的双曲保护法律系统提出了一个新颖的近似战略,目的是代表强烈互动不连续的动态。我们的方法目标是在流中平滑的区域实现高精确度近似,同时确保在陡峭的梯度区域,特别是跨冲击区域保持稳健和非螺旋行为。在“多层面最佳秩序检测”(MOD)(Clain等人,2011年比较物理杂志;Diot等人,2012年计算机和流流)之后,通过高阶准确的清晰计划(Abgrall,2017年科学计算杂志;Abgrall等人,计算机和数学与2018年应用区域保持高度的精确度。一个所谓的探测器确定候选人解决方案是否显示出任何刺激的振荡或数字问题,如果是这样的话,只有麻烦的细胞通过更具争议性的办法在当地重新被解读,计算机和流(2012年计算机和流),一个候选人解决方案在下一个时间水平上通过高阶的准确度精确度直径直径直径直的直径直径直径直径直径直径直径直径直径直径直径直径直的直径直径直径直径直径直径直径直径直的直直直径直直直直直径直直的直的直直直直直直直直直直直直直直的直的直直直直直直直向下向下直的直的直的直向下, 。