The variational multiscale method thought as an implicit large eddy simulation model for turbulent flows has been shown to be an alternative to the widely used physical-based models. This method is traditionally combined with equal-order velocity-pressure pairs, since it provides pressure stabilization. In this work, we consider a different approach, based on inf-sup stable elements and convection-only stabilization. In order to do so, we consider a symmetric projection stabilization of the convective term using an orthogonal subscale decomposition. The accuracy and efficiency of this method compared with residual-based algebraic subgrid scales and orthogonal subscales methods for equal-order interpolation is assessed in this paper. Moreover, when inf-sup stable elements are used, the grad-div stabilization term has been shown to be essential to guarantee accurate solutions. Hence, a study of the influence of such term in the large eddy simulation of turbulent incompressible flows is also performed. Furthermore, a recursive block preconditioning strategy has been considered for the resolution of the problem with an implicit treatment of the projection terms. Two different benchmark tests have been solved: the Taylor-Green Vortex flow with Re=1600, and the Turbulent Channel Flow at Reτ=395 and Reτ=590.
|Number of pages||25|
|Journal||Computer Methods in Applied Mechanics and Engineering|
|Publication status||Published - 1 Jun 2016|
- Block recursive preconditioning
- Grad-div stabilization
- Large eddy simulation
- Variational multiscale