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This chapter summarizes the activities of EADS-CASA in the FLOMANIA Project, providing some highlights about the implementations and results carried out using the in-house EMENS code. Among the computations performed, the MRTT (which is reported separately), the NACA0012 with round tip, the Obi diffuser and the RAE2822 airfoil are reported. The implementations include the SALSA TM and two types of wall functions: the Scalable WF and the Automatic WF. We are grateful to the TUB for their support with the SALSA; and we are also grateful to the INTA, which shares with EADS-CASA the EMENS code, for their collaboration in many aspects of the implementations.

Flows with massive separation are challenging for conventional URANS turbulence models. In this study the flow about a NACA0012 airfoil was computed over a range of angles of attack (α) varying from zero to ninety degrees for both URANS and DES models. The detailed analysis at α = 60 degrees is presented in this section. The DES methods are compared against their parent URANS models and it is seen that for this separated flow, DES methods outperform their URANS counterparts.

Here we briefly review the two numerical methods used by DLR during the FLOMANIA project as well as some remarks on the turbulence models available in these codes including some remarks on the implementation of DES and RSM. Furthermore some additional results obtained with the latter models are presented which are not mentioned elsewhere in this book.

The present chapter concisely describes the hybrid methods as applied in FLOMANIA by different partners. In the first chapter the non-zonal DES method is described, whereas in the second chapter the zonal approaches are presented. Beginning with a description of the general idea of the method in the chapter on DES an overview of existing versions is presented.

This chapter describes the common effort of UMIST, EADS-CASA, ALENIA and TUB to compute the steady vortex evolving at the round tip of a wing at 10° angle of attack. Results for different numerical grids obtained by the aforementioned four partners using a variety of codes and turbulence models are presented in comparison to experimental data. The main parameters of influence and suggestions for future computations of that case are identified.

The main objective of the present study is to analyse the turbulence properties in unsteady, strongly detached flows and to provide a database for improvement and validation of turbulence models, concerning the present class of non-equilibrium flows. The flow around a circular cylinder with a low aspect ratio (L/D=4.8) and a high blockage coefficient (D/H=0.208) is investigated. This confined environment is used in order to allow direct comparisons with realisable 3D Navier-Stokes computations avoiding ‘infinite’ conditions. The flow is investigated in the critical regime at Reynolds number 140,000. A cartography of the velocity fields in the near wake of the cylinder is obtained by the 2D Particle Image Velocimetry. Statistical mean (Reynolds averaged) and phase-averaged quantities are determined. Furthermore, POD analysis is performed on the data set in order to extract coherent structures of the flow and to compare the results with those obtained by the conditional sampling technique. The Reynolds stresses, the strain-rate and vorticity fields as well as the turbulence production terms are determined. These physical quantities where not measured in this detail up to now, to our knowledge and they are very useful for the development of advanced turbulence modelling techniques for unsteady flows. Based on the IMFT’s circular cylinder test-case, computations are carried out by advanced statistical turbulence modelling and by DES. The partners involved are IMFT and STPU.

Flows with massive separation are challenging for conventional URANS turbulence models. In this study the flow about a NACA0012 airfoil was computed over a range of angles of attack (α) varying from zero to ninety degrees for both URANS and DES models. The detailed analysis at α = 60 degrees is presented in this section. The DES methods are compared against their parent URANS models and it is seen that for this separated flow, DES methods outperform their URANS counterparts.

The present chapter presents the results obtained by Dassault, DLR and NUMECA for the ONERA M6 wing. Solutions by structured and unstructured methods are compared, where different turbulence models have been applied ranging from one-equation to full Reynolds stress models.

The flow in wind tunnel past OAT15A profile has been computed with WJ-H, Sm95 and Sm97 turbulence models. In the computations made with Sm95 model, a too aft shock position was obtained on the profile at symmetry plane. The shock location was correctly predicted by Sm97, while the results obtained with WJ-H showed a slightly upstream position of the shock wave. Equivalent results, in terms of Cp distributions, were obtained with the two latter models on the upper and lower wind tunnel walls, according with the experimental data. In evaluating the results, it should be taken in account that inflow-outflow boundary conditions were not exactly equivalent in DA and ALA computations, as ALA imposed a constant inflow profile and a different outflow pressure. In both cases, however, a correct boundary layer thickness at the entrance of the test section was obtained, so that the effect of wind tunnel blockage was properly taken in account.

However, for a careful simulation of velocity components in the airfoil wake, and hence a meaningful comparison with the experiment, the experimental inflow velocity and turbulence profiles and outflow pressure distribution should be carefully matched.

Flows with massive separation are challenging for conventional URANS turbulence models. In this study the flow about a NACA0012 airfoil was computed over a range of angles of attack (α) varying from zero to ninety degrees for both URANS and DES models. The detailed analysis at α = 60 degrees is presented in this section. The DES methods are compared against their parent URANS models and it is seen that for this separated flow, DES methods outperform their URANS counterparts.