We consider a pressure correction temporal discretization for the incompressible Navier-Stokes equations in EMAC form. We prove stability and error estimates for the case of mixed finite element spatial discretization, and in particular that the Gronwall constant's exponential dependence on the Reynolds number is removed (for sufficiently smooth true solutions) or at least significantly reduced compared to the commonly used skew-symmetric formulation. We also show the method preserves momentum and angular momentum, and while it does not preserve energy it does admit an energy inequality. Several numerical tests show the advantages EMAC can have over other commonly used formulations of the nonlinearity. Additionally, we discuss extensions of the results to the usual Crank-Nicolson temporal discretization.
翻译:我们用 EMAC 形式对压性纳维埃-斯托克斯方程式进行压力校正时间分解。我们证明混合有限元素空间分解的稳定性和误差估计,特别是格伦沃尔常数对Reynolds 数的指数依赖性已经消除(为了足够顺利的真正解决方案),或者与常用的斜对称配方相比至少显著减少。我们还展示了这种方法保持了动力和角动力,虽然它不保存能量,但它确实承认能源不平等。一些数字测试显示,EMAC 相对于非线性的其他常用配方而言,其优势可能比其他常用的非线性配方更显著。此外,我们讨论将结果扩展至通常的 Clank- Nicolson 时间分解化。