In this work a robust discontinuous Galerkin (DG) solver for turbulent high-lift aerodynamic flows using the turbulence model of Spalart and Allmaras (SA) is developed. The application of DG discretizations to turbulent RANS flows is one of the most pressing issues facing high-order methods on unstructured grids. The issue is the result of non-smooth behavior of the turbulence model equation, w...

The Spalart and Allmaras turbulence model has been implemented in a numerical code to study the compressible turbulent flows, which the system of governing equations is solved with a finite volume approach using a structured grid. The AUSM scheme is used to calculate the inviscid fluxes. Different benchmark problems have been computed to validate the implementation and numerical results are sho...

in the present work a two dimensional numerical investigation of steam flows in a turbine blade passage is performed. a finite volume approach has been used and the pressure–velocity coupling is resolved using the simple algorithm. the purpose of this paper is to find that one of the used turbulent models is better for this kind of studies. a structured mesh arrangement with boundary layer mesh...

Reynolds-averaged Navier–Stokes (RANS) methods often cannot predict shock/turbulence interaction correctly. This may be because RANS models do not account for the unsteady motion of the shock wave that is inherent in these interactions. Previous work proposed a shock-unsteadiness correction that significantly improves prediction of turbulent kinetic energy amplification across a normal shock in...

A wall–distance–free version of the Spalart–Allmaras (SA) one–equation model is proposed to account for the distinct effects of low-Reynolds number (LRN) and wall proximity. The turbulent kinetic energy k and the dissipation rate ǫ are evaluated using the ν̃t–transport equation together with some empirical relations. The model coefficients/functions preserve the anisotropic characteristics of tu...

Turbulent flows are the most applicable cases that in recent years the researches have been focused on developing of solution methods. Incompressible turbulent flow is one of these cases which need to be taken in account. Solving the incompressible Navier-stokes equation because of elliptical characteristics has been led to some researches in this field recently. The ACM of Chorin [1] as a pre-...

The Spalart-Allmaras and the Menter SST k-ω turbulence models are shown to have the undesirable characteristic that, for fully turbulent computations, a transition region can occur whose extent varies with grid density. Extremely fine two-dimensional grids over the front portion of an airfoil are used to demonstrate the effect. As the grid density is increased, the laminar region near the nose ...

This paper presents a time-accurate procedure for computing unsteady aerodynamic forces on wings with a full-span oscillating control surface by using sheared grids. In this procedure, the flow is computed by solving the unsteady Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with the one-equation Spalart-Allmaras turbulence model. A module to model control surface oscillations...