Aerodynamic shape optimization based on high-fidelity models is a computational intensive endeavor. The majority of the computational time is spent in the flow solver, and in the gradient calculation. In this paper, we present two approaches for reducing the overall computational cost of the optimization. The techniques are tested using the Common Research Model wing benchmark defined by the Ae...

An adaptive method for high-order discretizations of the Reynolds-averaged NavierStokes (RANS) equations is examined. The RANS equations and Spalart-Allmaras (SA) turbulence model are discretized with a dual consistent, discontinuous Galerkin discretization. To avoid oscillations in the solution in under-resolved regions, particularly the edge of the boundary layer, artificial dissipation is ad...

In this paper, the continuous adjointmethod to compute shape sensitivities in aerodynamic designwith turbulence modeling is described and developed. The focus is on compressible flows described by the Reynolds-averaged Navier–Stokes equations and the classical Spalart–Allmaras model for turbulence. Turbulence modeling usually requires, in particular, computation of the distance to the surface. ...

Unlike in the case of high Reynolds number airfoil, selecting a turbulent closure model for low airfoil is still challenge. A used not necessarily suitable due to presence separation bubbles airfoil. In this study, we two simple models, Spalart-Allmaras and k- , calculating thrust coefficient as propeller determine their accuracy. It was found that there significant discrepancy between numerica...

We evaluate the applicability of a production computational fluid dynamics code for conducting detached eddy simulation for unsteady flows. A second-order accurate Navier-Stokes code developed at NASA Langley Research Center, known as TLNS3D, is used for these simulations. We focus our attention on high Reynolds number flow (Re = 5× 10 − 1.4× 10) past a circular cylinder to simulate flows with ...

This paper presents several test cases that were used to validate the implementation of two turbulence models in UNS3D code, an in-house code. The Shear Stress Transport model and Spalart–Allmaras model. These explored using numerical results generated by three computational fluid dynamics codes: NASA’s FUN3D CFL3D, UNS3D. Four considered: a flat plate case, airfoil near-wake, backward-facing s...

To improve the calculation of the flow properties of an aerospike nozzle, different turbulence models were investigated in this study. The primary shape of the nozzle plug is determined through utilizing an approximate method. The flow field is, then, simulated using the Navier-Stokes equations for compressible flows. The commercial computational fluid dynamics code Fluent is used to simulate t...

The work presented in this article aims to the calculation of the aerodynamic characteristics of the NREL phase II rotor that is a horizontal axis downwind wind turbine rotor and which is assumed to stand isolated in the space. The Reynolds averaged Navier-Stokes equations combined with the Spalart-Allmaras turbulence model that describes the three dimensional steady state flow about the wind t...