Balancing aspects of numerical dissipation, dispersion, and aliasing in time‐accurate simulations

Abstract

The current study looks at the selection of scheme elements that are well‐suited for long‐time integration of unsteady flows in the absence or under‐resolution of physical diffusion. A concerted assembly of numerical components are chosen relative to a target aliasing limit, which is taken as a best‐case scenario for overall spectral resolvability. High‐order and optimized difference stencils are employed in order to achieve accuracy; meanwhile, quasi skew‐symmetric splitting techniques for nonlinear transport terms are used in order to greatly improve robustness. Finally, tunable and scale‐discriminant artificial‐dissipation methods are incorporated for de‐aliasing purposes and as a means of further enhancing both accuracy and stability. Central finite difference methods are considered, and spectral characterizations of the scheme components are presented. Canonical test cases (the isentropic vortex [IV] and Taylor‐Green vortex problems) are chosen in order to highlight the benefits associated with the proposed approach for enhancing overall algorithm robustness and accuracy.

Document Details

Document Type
Pub Defense Publication
Publication Date
May 06, 2020
Source ID
10.1002/fld.4837

Entities

People

  • Ann Karagozian
  • Ayaboe Edoh
  • Nathan L. Mundis
  • Venkateswaran Sankaran

Organizations

  • Air Force Office of Scientific Research
  • Air Force Research Laboratory
  • Jacobs Engineering Group

Tags

Readers

  • Computational Fluid Dynamics (CFD)
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Image Processing and Computer Vision.