论文标题

三角形网格上双曲线PDE的高阶连续FEM的光谱分析:近似,稳定和时间步变的影响

Spectral analysis of high order continuous FEM for hyperbolic PDEs on triangular meshes: influence of approximation, stabilization, and time-stepping

论文作者

Michel, Sixtine, Torlo, Davide, Ricchiuto, Mario, Abgrall, Rémi

论文摘要

在这项工作中,我们研究了二维双曲部分偏微分方程的各种连续有限元离散化,从而改变了多项式空间(lagrangian在equalpaced上,lagrangian,lagrangian在正交点(立方体)和伯恩斯坦),稳定技术(稳定性),稳定性和稳定性损害,或者连续限制了损害,或者连续限制了限制)。 (Runge-Kutta(RK),坚固的稳定性保留RK和递延校正)。这是Michel S.等人Sci的一维研究的扩展。计算。 (2021),其结果不在多维框架中。该研究根据效率对这些方案进行排名(其中大多数是质量矩阵),稳定性和分散误差,提供了最佳的CFL和稳定系数。二维中的挑战与傅立叶分析有关。在这里,我们在两种类型的周期性三角网格上执行它,从而改变了对流的角度,并将所有结果结合在一起以进行一般稳定性分析。此外,我们引入了额外的高级粘度以稳定不连续性,以展示如何使用这些方法来测试实践兴趣。在线性和非线性问题上,所有理论结果均经过数值验证,并提供了错误CPU时间曲线。我们的最终结论表明,与SSPRK和OSS稳定相结合的立方体元素是最有希望的组合。

In this work we study various continuous finite element discretization for two dimensional hyperbolic partial differential equations, varying the polynomial space (Lagrangian on equispaced, Lagrangian on quadrature points (Cubature) and Bernstein), the stabilization techniques (streamline-upwind Petrov-Galerkin, continuous interior penalty, orthogonal subscale stabilization) and the time discretization (Runge-Kutta (RK), strong stability preserving RK and deferred correction). This is an extension of the one dimensional study by Michel S. et al J. Sci. Comput. (2021), whose results do not hold in multi-dimensional frameworks. The study ranks these schemes based on efficiency (most of them are mass-matrix free), stability and dispersion error, providing the best CFL and stabilization coefficients. The challenges in two-dimensions are related to the Fourier analysis. Here, we perform it on two types of periodic triangular meshes varying the angle of the advection, and we combine all the results for a general stability analysis. Furthermore, we introduce additional high order viscosity to stabilize the discontinuities, in order to show how to use these methods for tests of practical interest. All the theoretical results are thoroughly validated numerically both on linear and non-linear problems, and error-CPU time curves are provided. Our final conclusions suggest that Cubature elements combined with SSPRK and OSS stabilization is the most promising combination.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源