Advertisement

A Hybrid LES/CAA Method for Aeroacoustic Applications

  • Qinyin Zhang
  • Phong Bui
  • Wageeh A. El-Askary
  • Matthias Meinke
  • Wolfgang Schröder
Conference paper
  • 419 Downloads

Abstract

This paper describes a hybrid LES/CAA approach for the numerical prediction of airframe and combustion noise. In the hybrid method first a Large-Eddy Simulation (LES) of the flow field containing the acoustic source region is carried out from which then the acoustic sources are extracted. These are then used in the second computational Aeroacoustics (CAA) step in which the acoustic field is determined by solving linear acoustic perturbation equations. For the application of the CAA method to a unconfined turbulent flame, an extension of the method to reacting flow fields is presented. The LES method is applied to a turbulent flow over an airfoil with a deflected flap at a Reynolds number of Re = 106. The comparison of the numerical results with the experimental data shows a good agreement which shows that the main characteristics of the flow field are well resolved by the LES. However, it is also shown that a zonal LES which concentrates of the trailing edge region on a refined local mesh leads to a further improvement of the accuracy. In the second part of the paper, the CAA method with the extension to reacting flows is explained by an application to a non-premixed turbulent flame. The monopole nature of the combustion noise is clearly verified, which demonstrates the capability of the hybrid LES/CAA method for noise prediction in reacting flows.

Keywords

Large Eddy Simulation Airfoil Surface Combustion Noise Noise Prediction Total Time Derivative 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Ewert, R., Schröder, W.: On the simulation of trailing edge noise with a hybrid LES/APE method. J. Sound and Vibration 270 (2004) 509–524CrossRefGoogle Scholar
  2. 2.
    Wagner, S., Bareiß, R., Guidati, G.: Wind Turbine Noise. Springer, Berlin (1996)Google Scholar
  3. 3.
    Howe, M.S.: Trailing edge noise at low mach numbers. J. Sound and Vibration 225 (2000) 211–238CrossRefGoogle Scholar
  4. 4.
    Davidson, L., Cokljat, D., Fröhlich, J., Leschziner, M., Mellen, C., Rodi, W.: LESFOIL: Large Eddy Simulation of Flow Around a High Lift Airfoil. Springer, Berlin (2003)zbMATHGoogle Scholar
  5. 5.
    El-Askary, W.A.: Zonal Large Eddy Simulations of Compressible Wall-Bounded Flows. PhD thesis, Aerodyn. Inst. RWTH Aachen (2004)Google Scholar
  6. 6.
    Poinsot, T.J., Lele, S.K.: Boundary conditions for direct simulations of compressible viscous flows. J. Comp. Phys. 101 (1992) 104–129zbMATHCrossRefMathSciNetGoogle Scholar
  7. 7.
    Ewert, R., Meinke, M., Schröder, W.: Computation of trailing edge noise via LES and acoustic perturbation equations. Paper 2002–2467, AIAA (2002)Google Scholar
  8. 8.
    Schröder, W., Meinke, M., El-Askary, W.A.: LES of turbulent boundary layers. In: Second International Conference on Computational Fluid Dynamics ICCFD II, Sydney. (2002)Google Scholar
  9. 9.
    El-Askary, W.A., Schröder, W., Meinke, M.: LES of compressible wall bounded flows. Paper 2003–3554, AIAA (2003)Google Scholar
  10. 10.
    Schröder, W., Ewert, R.: Computational aeroacoustics using the hybrid approach (2004) VKI Lecture Series 2004–05: Advances in Aeroacoustics and Applications.Google Scholar
  11. 11.
    Würz, W., Guidati, S., Herr, S.: Aerodynamische Messungen im Laminarwindkanal im Rahmen des DFG-Forschungsprojektes SWING+ Testfall 1 und Testfall 2 (2002) Inst. für Aerodynamik und Gasdynamik, Universität Stuttgart.Google Scholar
  12. 12.
    Strahle, W.C.: Some results in combustion generated noise. J. Sound and Vibration 23 (1972) 113–125CrossRefGoogle Scholar
  13. 13.
    Crighton, D., Dowling, A., Williams, J.F.: Modern Methods in analytical acoustics, Lecture Notes. Springer, Berlin (1996)Google Scholar
  14. 14.
    Ewert, R., Schröder, W.: Acoustic perturbation equations based on flow decomposition via source filtering. J. Comp. Phys. 188 (2003) 365–398zbMATHCrossRefGoogle Scholar
  15. 15.
    Bui, T.P., Meinke, M., Schröder, W.: A hybrid approach to analyze the acoustic field based on aerothermodynamics effects. In: Proceedings of the joint congress CFA/DAGA’ 04, Strasbourg. (2004)Google Scholar
  16. 16.
    Kotake, S.: On combustion noise related to chemical reactions. J. Sound and Vibration 42 (1975) 399–410CrossRefGoogle Scholar
  17. 17.
    Germano, M., Piomelli, U., Moin, P., Cabot, W.H.: A dynamic subgrid-scale viscosity model. Phys. of Fluids 7 (1991) 1760–1765Google Scholar
  18. 18.
    Waterson, N.P.: Development of a bounded higher-order convection scheme for general industrial applications. In: Project Report 1994–33, von Karman Institute. (1994)Google Scholar
  19. 19.
    Klein, M., Sadiki, A., Janicka, J.: A digital filter based generation of inflow data for spatially developing direct numerical or large eddy simulations. J. Comp. Phys. 186 (2003) 652–665zbMATHCrossRefGoogle Scholar
  20. 20.
    Düsing, M., Kempf, A., Flemming, F., Sadiki, A., Janicka, J.: Combustion les for premixed and diffusion flames. In: VDI-Berichte Nr. 1750, 21. Deutscher Flammentag, Cottbus. (2003) 745–750Google Scholar
  21. 21.
    Tam, C.K.W., Webb, J.C.: Dispersion-relation-preserving finite difference schemes for computational acoustics. J. Comp. Phys. 107 (1993) 262–281zbMATHCrossRefMathSciNetGoogle Scholar
  22. 22.
    Hu, F.Q., Hussaini, M.Y., Manthey, J.L.: Low-dissipation and low-dispersion runge-kutta schemes for computational acoustics. J. Comp. Phys. 124 (1996) 177–191zbMATHCrossRefMathSciNetGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Qinyin Zhang
    • 1
  • Phong Bui
    • 1
  • Wageeh A. El-Askary
    • 1
  • Matthias Meinke
    • 1
  • Wolfgang Schröder
    • 1
  1. 1.Institute of AerodynamicsRWTH AachenAachenGermany

Personalised recommendations