论文标题
具有灵活的非线性耗散控制的低径流冲击框架
A low-dissipation shock-capturing framework with flexible nonlinear dissipation control
论文作者
论文摘要
在这项工作中,提出了一个框架,用于构建具有灵活且可控制的非线性耗散的任意高阶低径流冲击方案,以解决对流为主的问题。虽然构建了一组候选宽度的候选模具,但每个候选模型都通过针对目标的基本非振荡(TENO)方案提出的ENO样模型选择程序表示为光滑或非平滑,[Fu et al。,计算物理学杂志,305(2016):333-359]。非平滑候选者不是直接被丢弃,而是被额外的非线性限制器(例如单调性保留(MP)限制器或总变化减小(TVD)限制器过滤。因此,高阶重建是通过将候选通量组装成最佳的线性权重来实现的,因为它们要么是光滑的重建,要么具有良好的非振荡特性的过滤效果。与标准Teno范式一样,重新归一化程序是不需要的。这个新的框架将Teno,WENO和其他非线性限制器的概念串联以进行冲击,并为设计低衰减非线性方案提供了新的见解。通过对非线性限制器的适应,可以分别控制新提出的框架中的非线性耗散,而不会影响平滑区域的性能。根据提议的框架,提出了一个具有可控耗散的新的六点和八点非线性方案。模拟了一组涉及强烈不连续性和宽带波动的关键基准案例。数值结果表明,提出的新方案迅速捕获了不连续性,并以低消散的方式解决了高波动的波动,同时保持平滑区域中所需的准确性顺序。
In this work, a framework to construct arbitrarily high-order low-dissipation shock-capturing schemes with flexible and controllable nonlinear dissipation for convection-dominated problems is proposed. While a set of candidate stencils of incremental width is constructed, each one is indicated as smooth or nonsmooth by the ENO-like stencil selection procedure proposed in the targeted essentially non-oscillatory (TENO) scheme [Fu et al., Journal of Computational Physics 305 (2016): 333-359]. Rather than being discarded directly as with TENO schemes, the nonsmooth candidates are filtered by an extra nonlinear limiter, such as a monotonicity-preserving (MP) limiter or a total variation diminishing (TVD) limiter. Consequently, high-order reconstruction is achieved by assembling candidate fluxes with optimal linear weights since they are either smooth reconstructions or filtered ones which feature good non-oscillation property. A weight renormalization procedure as with the standard TENO paradigm is not necessary. This new framework concatenates the concepts of TENO, WENO and other nonlinear limiters for shock-capturing, and provides a new insight to designing low-dissipation nonlinear schemes. Through the adaptation of nonlinear limiters, nonlinear dissipation in the newly proposed framework can be controlled separately without affecting the performance in smooth regions. Based on the proposed framework, a family of new six- and eight-point nonlinear schemes with controllable dissipation is proposed. A set of critical benchmark cases involving strong discontinuities and broadband fluctuations is simulated. Numerical results reveal that the proposed new schemes capture discontinuities sharply and resolve the high-wavenumber fluctuations with low dissipation, while maintaining the desired accuracy order in smooth regions.