论文标题
带有接口条件强制执行的不连续的Galerkin有限元法,用于可压缩粘性流动
The Moving Discontinuous Galerkin Finite Element Method with Interface Condition Enforcement for Compressible Viscous Flows
论文作者
论文摘要
带有接口条件强制执行(MDG-ICE)的不连续的Galerkin有限元法被应用于粘性流的情况。该方法使用一种弱公式,该公式分别执行保护定律,构造定律和相应的界面条件,以提供检测界面或解决不足的流量特征的手段。为了满足由此产生的过度确定的弱配方,将离散的域几何形状作为变量引入,以便该方法隐含地符合先验的未知接口,并移动网格以解决尖锐而光滑的梯度,以实现一种各种型号曲线库Villinear $ r $ r $ - 适应性。这种方法避免了使用冲击捕获,人工耗散或限制引入的低阶错误。该方法的实用程序是将其应用于一系列测试问题的应用,最终将可压缩的Navier-Stokes解决方案用于二维空间中的Reynolds $ 10^{5} $的Mach 5粘性弓箭冲击。不稳定问题的时间精确解决方案是通过时空公式获得的,其中不稳定问题被公式化为较高维度的稳定时空问题。该方法显示可准确解决和运输粘性结构,而无需依赖数值耗散进行稳定。
The moving discontinuous Galerkin finite element method with interface condition enforcement (MDG-ICE) is applied to the case of viscous flows. This method uses a weak formulation that separately enforces the conservation law, constitutive law, and the corresponding interface conditions in order to provide the means to detect interfaces or under-resolved flow features. To satisfy the resulting overdetermined weak formulation, the discrete domain geometry is introduced as a variable, so that the method implicitly fits a priori unknown interfaces and moves the grid to resolve sharp, but smooth, gradients, achieving a form of anisotropic curvilinear $r$-adaptivity. This approach avoids introducing low-order errors that arise using shock capturing, artificial dissipation, or limiting. The utility of this approach is demonstrated with its application to a series of test problems culminating with the compressible Navier-Stokes solution to a Mach 5 viscous bow shock for a Reynolds number of $10^{5}$ in two-dimensional space. Time accurate solutions of unsteady problems are obtained via a space-time formulation, in which the unsteady problem is formulated as a higher dimensional steady space-time problem. The method is shown to accurately resolve and transport viscous structures without relying on numerical dissipation for stabilization.