ASSESSMENT OF URANS AND DES SIMULATIONS FOR TWO-DIMENSIONAL BACKWARD FACING STEP FLOW

2차원 후항계단유동에 대한 URANS와 DES의 수치해석 평가

  • Published : 2006.06.01

Abstract

A two-dimensional backward facing step flow is simulated by using URANS and Detached Eddy Simulations(DES) approaches. Turbulence models adopted for URANS and DES simulations are Spalart-Allmaras(S-A) model and Shear Stress Transport(SST) model. The target flow with ER=1.125, $Re_H=37,500$ is experimentally studied by Driver & Seegmiller. Various versions of DES have been tested in this paper. Results of the simulations are compared with the experimental data available to evaluate the merits and demerits of URANS and several versions of DES. URANS simulation converges to a steady state and hence unsteady characteristics are not featured. DES simulations in general successfully mimic large scale structures and oscillation characteristics of the flow.

Keywords

References

  1. Eaton, J.K. and Johnston, J.P., 1981, "A review of research on subsonic turbulent flow reattachment," AIAA J., Vol.19, No.9, p.1093-1100 https://doi.org/10.2514/3.60048
  2. Driver, D.M. and Seegmiller, H.L., 1985, "Features of a Reattaching Turbulent Shear Layer in Divergent Channel Flow," AIAA J., Vol.23, No.2, p.163-171 https://doi.org/10.2514/3.8890
  3. Neto, A.S., Grand, D., Metais, O. and Lesieur, M., 1993, "A numerical investigation of the coherent vortices in turbulence behind a BFS," Journal of Fluid Mechanics, Vol.256, p.1-25 https://doi.org/10.1017/S0022112093002691
  4. Spalart, P.R., Jou, W.H., Strelets, M. and Allmaras, S.R., 1997, "Comments on the feasibility of LES for wings and on a hybrid RANS/LES approach," Advances in DNS /LES:First AFOSR Int. Conf. on DNS/LES, edited by C. Liu and Z. Liu, Greyden, Columbus
  5. Strelets, M., 2001, "Detached eddy simulation of massively separated flows," AIAA paper 2001-0879
  6. Jovic, S. and Driver, D.M., 1995, "Reynolds number effects on skin friction in separated flows behind a backward facing step," Experiments in Fluids, Vol.18, p.87-92
  7. Spalart, P.R. and Allmaras, S.R., 1993, "A one equation turbulence model for aerodynamic flow," AIAA paper 1992-0439
  8. Menter, F.R., 1993, "Zonal two-equation k-omega turbulence models for aerodynamic flow," AIAA paper 1993-2906
  9. Travin, A., Shur, M., Strelets, M. and Spalart, P.R., 2000, "Physical and numerical upgrades in the detached-eddy simulation of complex turbulent flows," EUROMECH Colloquium on LES of complex transitional and turbulent flows
  10. Mittal, R. and Moin, P., 1997, "Stability of Upwind-biased finite difference schemes for Large Eddy Simulation of turbulent flows," AIAA J., Vol.35, No.8, p.1415-1417 https://doi.org/10.2514/2.253
  11. NPARC Ailliance validation site (NASA) (http://www.grc.nasa.gov/WWW/wind/valid/validation.html)
  12. Kumar, S. and Loth, E., 2001, "Detached eddy simulations of an iced-airfoil," AIAA paper, 2001-0678
  13. Driver, D.M., Seegmiller, H.L. and Marvin, J.G., 1987, "Time-Dependent Behavior of a Reattaching Shear Layer," AIAA J., Vol.25, No.7, p.914-919 https://doi.org/10.2514/3.9722
  14. Eaton, J.K. and Johnston, J.P., 1982, "Low frequency unsteadyness of a reattaching turbulent shear layer," Turbulent Shear Flows, vol.3, p.162-170
  15. Hunt, J.C.R., Wray, A.A. and Moin, P., 1998, "Eddies stream and convergence zones in turbulent flows," in Proceedings of the 1998 Summer Program(CTR), p.193-208