Aerodynamic Performance Improvement by Divergent Trailing Edge Modification to a Supercritical Airfoil

  • Yoo, Neung-Soo (Division of Mechanical Engineering and Mechatronics, Kangwon National University)
  • Published : 2001.10.01

Abstract

A computational study has been performed to determine the effects of divergent trailing edge (DTE) modification to a supercritical airfoil in transonic flow field. For this, the computational result with the original DLBA 186 supercritical airfoil was compared to that of the modified DLBA 283. A wavier-Stokes code, Fluent 5. 1, was used with Spalart-Allmaras's one-equation turbulence model. Results in this study showed that the reduction in drag due to the DTE modification is associated with weakened shock and delayed shock appearance. The decrease in drag due to the DTE modification is greater than the increase in base drag. The effect of the recirculating flow region on lift increase was also observed. An airfoil with DTE modification achieved the same lift coefficient at a lower angle of attack while giving a lower drag coefficient. Thus, the lift-to-drag ratio increases in transonic flow conditions compared to the original airfoil. The lift coefficient increases considerably whereas the lift slope increases just a little due to DTE modification.

Keywords

References

  1. Henne, P. A., and Gregg, R. D., 1991, 'New Airfoil Design Concept,' Journal of Aircraft, Vol. 28, No. 5, pp. 300-311
  2. Henne, P. A., 1990, 'Innovation with Com-putational Aerodynamics : The Divergent Trailing Edge Airfoil,' Applied Computational Aerodynamics, edited by P. A. Henne, AIAA Inc., Washington, D. C, pp. 221-261
  3. Jiang, Y. T., Damodaran, M. and Lee, K. H., 1997, 'High-Resolution Finite Volume Computation of Turbulent Transonic Flow past Airfoils,' AIAA J, Vol. 35, No. 7, pp. 1134 -1142
  4. Kline, S. J., Cantwell, B. J., and Lilley, G. M.Editors, 1980, '1980-81 AFOSR HTTMStanford Conference on Complex TurbulentFlows: Comparison of Computation andExperiments,' Thermosciences Division, Mechanical Engineering Dept., Stanford University, Stanford, California
  5. Lotz, R. D., 1995, 'Grid Dependence and Numerical Uncertainty Analysis of a Transonic Airfoil Calculation,' MS Degree Thesis, R.P.I., New York
  6. Roache, P. J., 1998, 'Verification of Codes and Calculations,' AIAA Journal, Vol. 36, No. 5, pp. 696-702
  7. Strelets, M. Kh., Travin, A. K. and Shur, M. L., 1997, 'A Computation between One and Two -Equation Differential Models of Turbulence in Application to Separated and Attached Flows: Transonic Flow Around Airfoil,' High Temperature, Vol. 35, No. 2, pp. 298-310
  8. Thompson, B. E., and Whitelaw, J. H., 1989, 'Trailing-Edge Region of Airfoils,' Journal of Aircraft, Vol. 26, No. 3, pp. 225-234
  9. Yoo, N. S., 2000, 'Effect of the Gurney Flap on a NACA 23012 Airfoil,' KSME International Journal, Vol. 14, No. 9, pp. 1013-1019