DOI QR코드

DOI QR Code

An Experimental Study on Drag Reduction of Grooved Cylinders

Riblet 홈을 가진 원주의 저항감소에 관한 실험적 연구

  • Published : 2001.02.01

Abstract

Wake structures behind two circular cylinders with different groove configurations(U and V-shape) have been investigated experimentally. The results were compared with those for the smooth cylinder having the same diameter D. The drag force, mean velocity and turbulent intensity profiles of wake behind the cylinders were measured with varying the Reynolds number in the range of Re(sub)D=8,000∼14,000. As a result, the U-shaped groove was found to reduce the drag up to 18.6%, but the V-shaped groove reduced drag force only 2.5% compared with the smooth cylinder. As the Reynolds number increases, the vortex shedding frequency becomes a little larger than that of the smooth cylinder. The visualized flow using the smoke-wire and particle tracing methods shows the flow structure qualitatively.

Keywords

Riblet;Drag Reduction;Grooved Cylinder;Flow Control;Flow Visualization

References

  1. Strouhal, V., 1878, 'Uber eine Besondere Art der Tonerregung,' Ann. Physik(Leipzig)
  2. Tucker, V., and Parrott, G. C., 1970, 'Aerodynamics of Gliding Flight of Falcons and Other Birds,' J. Exp. Biol., Vol. 52, pp. 345-368
  3. Lee, S. J., Lee, S. H., 1999, 'Synchronized Smoke-Wire Technique for Flow Visualization of Turbulent Flows,' J. of Flow Visualization and Image Processing, Vol. 6, pp. 65-78
  4. White, F. M., 1986, Fluid Mechanics, McGraw-Hill
  5. Stansby, P. K., 1974, 'The Effect of Endplates on the Base Pressure Coefficient of a Circular Cylinder,' Aeronautical J., Vol. 78, pp. 36-37
  6. Perry, A. E., 1982, Hot-Wire Anemometry, Clarendon Press Oxford
  7. Lee, S. J., Lee, S. H., 2000, 'Flow Field Analysis of Turbulent Boundary Layer over a Riblet Surface,' Exp. in Fluids, Vol. 29, in press
  8. 이상현, 이상준, 1999, '반원형 리블렛 상부 난류 경계층의 유동구조 연구,' KSME J., 23, pp. 937-944
  9. Choi, H. C., Moin, P. and Kim, J., 1993, 'Direct Numerical Simulation of Laminar and Turbulent Flow over Riblets,' J. Fluid Mech., Vol. 255, pp. 503-539
  10. Leung, Y. C., Ko, N. W. M., 1991, 'Near Wall Characteristics of Flow over Grooved Circular Cylinder,' Exp. in Fluids, Vol. 10, pp. 322-332
  11. Ko, N.W.M., Leung, Y.C., and Chen, J.J.J., 1986, 'Flow Past V-Groove Circular Cylinder,' AIAA Journal, Vol. 25, No. 6, pp. 806-811
  12. Guven, O., Farell, C., Patel, V. C., 1980, 'Surface Roughness Effects on the Mean Flow Past Circular Cylinders,' J. Fluid Mech., Vol. 98, pp. 673-701 https://doi.org/10.1017/S0022112080000341
  13. Choi, K. S., 1989, 'Near-Wall Structure of a Turbulent Boundary Layer with Riblets,' J. Fluid Mech., Vol. 208, pp. 417-458 https://doi.org/10.1017/S0022112089002892
  14. Achenbach, E., 1971, 'Influence of Surface Roughness on the Crossflow Around a Circular Cylinder,' J. Fluid Mech., Vol. 46, pp. 321-335 https://doi.org/10.1017/S0022112071000569
  15. Bacher, E. V. and Smith, C. R., 1986, 'Turbulent Boundary Layer Modification by Surface Riblets,' AIAA Journal, Vol. 24, No. 8, pp. 1382-1385
  16. Robert, J. P., 1992, 'Drag Reduction: an Industrial Challenge,' Proceedings of Special Course on Skin Friction Drag Reduction, Brussels, AGARD-VKI
  17. Walsh, M. J., 1983, 'Riblets as a Viscous Drag Reduction Technique,' AIAA Journal, Vol. 21, No. 4, pp. 485-486
  18. Cantwell, B. J., 1981, 'Organized Motion in Turbulent Flow,' Annual Rev. Fluid Mech., 13, pp. 457-515 https://doi.org/10.1146/annurev.fl.13.010181.002325
  19. Robinson, S. K., 1991, 'Coherent Motions in the Turbulent Boundary Layer,' Annual Rev. Fluid Mech., 23, pp. 601-639 https://doi.org/10.1146/annurev.fl.23.010191.003125
  20. Gad-el-Hak, M., 1989, 'Flow Control,' Appl. Mech. Rev., 42, pp. 261-293
  21. Walsh, M. J., 1982, 'Turbulent Boundary Layer Drag Reduction Riblets,' AIAA paper 82-0169