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Detached-Eddy Simulation of Vortex Generator Jet Using Chimera Grids

Authors: Saqib Mahmood, Rolf Radespiel


This paper aims at numerically analysing the effect of an active flow control (AFC) by a vortex generator jet (VGJ) submerged in a boundary layer via Chimera Grids and Detached- Eddy Simulation (DES). The performance of DES results are judged against Reynolds-Averaged Navier-Stokes (RANS) and compared with the experiments that showed an unsteady vortex motion downstream of VGJ. Experimental results showed that the mechanism of embedding logitudinal vortex structure in the main stream flow is quite effective in increasing the near wall momentum of separated aircraft wing. In order to simulate such a flow configuration together with the VGJ, an efficient numerical approach is required. This requirement is fulfilled by performing the DES simulation over the flat plate using the DLR TAU Code. The DES predictions identify the vortex region via smooth hybrid length scale and predict the unsteady vortex motion observed in the experiments. The DES results also showed that the sufficient grid refinement in the vortex region resolves the turbulent scales downstream of the VGJ, the spatial vortex core postion and nondimensional momentum coefficient RVx .

Keywords: DES, RANS, VGJ, Chimera Grid

Digital Object Identifier (DOI):

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[1] X. Zhang, Co and Contrarotaing Streamwise Vortices in a Turbulent Boundary Layer, Journal of Aircraft, September-October 1995, Vol. 32, No. 5, pp. 1095-1101.
[2] J. Ortmanns, C.J. K¨ahler, A Single Round Vortex Generator Jet at High Reynolds Number, FLUCOME 2007, Tallahassee, Florida, USA.
[3] J. Ortmanns, Aktive Grenzschichtbeeinflussung mittels pneumatischer Wirbelgeneratoren bei groen Reynoldszahlen, Institut f¨ur Str¨omungsmechanik, TU Braunschweig, Dissertation ZLRForchungsbericht 2009-03.
[4] S. Mahmood, R. Radespiel, RANS simulation of jet actuation in a boundary layer flow using Chimera grids, Deutscher Luft- und Raumfahrtkongress 2009, September 8-10, Aachen, 2009.
[5] P. R. Spalart, Young person-s guide to detached-eddy simulation grids, NASA CR-2001-211032.
[6] P. R. Spalart, S. Deck, M. Shur, K.D. Squires, M. Strelets, A. Travin, A new version of detached-eddy simulation, resistant to ambiguous grid densities, Theoretical and Computational Fluid Dynamics, Vol. 20, No. 3, pp. 181-195, 2006.
[7] S. Deck, E. Garnier, Detached and large eddy simulation of unsteady side-loads over an axisymmetric afterbody. Proceedings of 5th European Symposium on aerothermodynamics for space vehicles. Cologne, Germany, November 8-11, 2004.
[8] C. P. Mellen, J. Fr¨ohlich, W. Rodi, Lessons from the European LESFOIL project on LES of flow around an airfoil, AIAA Journal, Vol. 41, No. 4, pp. 573-581, 2003.
[9] A. Travin, M. Shur, P.R. Spalart, M. Strelets, Improvement of delayed detaced-eddy simulation for LES with wall modelling, ECCOMAS CFD 2006. In: Wesseling, P., O˜nate,E., P'eriaux, J. (Eds.), Proceedings (CDROM) of the European Conference on Computational Fluid Dynamics ECCOMAS CFD 2006, Egmond aan Zee, The Netherlands.
[10] M. Shur, P. R. Spalart, M. Strelets, A. Travin, A hybrid RANSLES approach with delayed-DES and wall-modelled LES capabilities, International Journal of Heat and Fluid Flow 29 (2008)1638 − 1649.
[11] P. R. Spalart, W.-H. Jou, M. Strelets, S.R. Allmaras, Comments on the feasibility of LES for wings, and on a hybrid RANS/LES approach, First AFOSR International Conference on DNS/LES, August 4-8, 1997, Ruston, Louisiana.
[12] P. R., Spalart, Strategies for turbulence modelling and simulations, Int. J. Heat Fluid Flow, 21, 252−263 (2000).
[13] M. Strelets, Detached Eddy Simulation of massively separated flows, AIAA Paper, AIAA − 2001 − 879 (2001).
[14] T. Gerhold, O. Friedrich, J. Evans, M. Galle, Calculation of Complex Three-Dimensional Configurations Employing the DLR TAU-Code, 1997, AIAA-paper 97-0167.
[15] D. Schwamborn, T. Gerhold, R. Heinrich, The DLR TAU-Code: Recent applications in research and industry, ECCOMAS CFD 2006 CONFERENCE, September 04-08, 2006, Netherlands.
[16] A. Madrane, A. Raichle, A. Stuermer, Parallel implementation of a dynamic overset unstructured grid approach, ECCOMAS 2004, Jyv¨askyl¨a, July 24-28, 2004.
[17] T. Schwarz, An Interpolation Method Maintaining the Wall Distance for Structured and Unstructured Overset Grids. In: Proceedings of the CEAS 2009 conference. CEAS 2009 European Air and Space Conference, October 26-29, 2009, Manchester, UK.
[18] Commercial CFD software package by POINTWISE, Inc.
[19] Norddeutscher Verbund f¨ur Hoch und H¨ochsleistungsrechnen,, 2011.
[20] P. Spalart, and S. Allmaras, A one-equation turbulence model for aerodynamic flows, La Recherche Aerospatiale, 1994, pp. 5-21.
[21] F. MENTER, Improved two-equation turbulence models for aerodynamic flows, 1992, Tech. Report TM 103975, NASA, NASA Langley Research Center, Hampton, VA 23681-2199.