Traditional finite element approaches are well-known to introduce spurious oscillations when applied to advection-dominated problems. We explore alleviation of this issue from the perspective of a generalized finite element formulation, which enables stabilization through an enrichment process. The presented work uses solution-tailored enrichments for the numerical solution of the one-dimensional, unsteady Burgers equation. Mainly, generalizable exponential and hyperbolic tangent enrichments effectively capture local, steep boundary layer/shock features. Results show natural alleviation of oscillations and return smooth numerical solutions over coarse grids. Additionally, significantly improved error levels are observed compared to Lagrangian finite element methods.
翻译:众所周知,传统的有限元素方法在应用于对流占支配地位的问题时会引入虚假的振动。我们从普遍有限元素配方的角度探讨这一问题的缓解问题,这种配方能够通过浓缩过程实现稳定。介绍的工作使用解决方案定制的浓缩物,用于单维、不稳定的布尔格斯方程式的数值解决方案。主要是,可普及化的指数和双曲相切质浓缩物有效捕捉到局部、陡峭的边界层/冲击特征。结果显示振动自然减缓,并在粗糙的电网上返回平滑的数字解决方案。此外,观察到与拉格朗基亚的限定元素方法相比,误差水平显著提高。