Title

An Optimally Accurate Discrete Regularization for Second Order Timestepping Methods for Navier-Stokes Equations

Abstract

We propose a new, optimally accurate numerical regularization/stabilization for (a family of) second order timestepping methods for the Navier-Stokes equations (NSE). The method combines a linear treatment of the advection term, together with stabilization terms that are proportional to discrete curvature of the solutions in both velocity and pressure. We rigorously prove that the entire new family of methods are unconditionally stable and O(ĝt2) accurate. The idea of 'curvature stabilization' is new to CFD and is intended as an improvement over the commonly used 'speed stabilization', which is only first order accurate in time and can have an adverse effect on important flow quantities such as drag coefficients. Numerical examples verify the predicted convergence rate and show the stabilization term clearly improves the stability and accuracy of the tested flows.

Department(s)

Mathematics and Statistics

Comments

The first author is partially supported by Air Force grant FA 9550-12-1-0191 . The second author is partially supported by NSF Grant DMS15222191 . The third author is partially supported by NSF Grant DMS1522191 and US Army Grant 65294-MA . The fourth author is partially supported by Air Force grant FA 9550-12-1-0191 and NSF grant DMS-1522574 .

Keywords and Phrases

Computational fluid dynamics; Drag; Finite difference method; Numerical methods; Stabilization; BDF2; Discrete regularization; IMEX methods; Second order convergence; Speed stabilization; Time stepping method; Unconditional stability; Unconditionally stable; Navier Stokes equations; Crank–Nicolson; Navier–Stokes

International Standard Serial Number (ISSN)

0045-7825

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2016 Elsevier, All rights reserved.

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