DOI QR코드

DOI QR Code

Investigation of passive flow control on the bluff body with moving-belt experiment

Rho, Joo-Hyun;Lee, Dongho;Kim, Kyuhong

  • Received : 2015.05.22
  • Accepted : 2016.06.13
  • Published : 2016.06.30

Abstract

The passive control methods such as horizontal and vertical fences on the lower surface of the bluff body were applied to suppress the vortex shedding and enhance the aerodynamic stability of flow. For investigating the effects of the passive control methods, wind tunnel experiments on the unsteady flow field around a bluff body near a moving ground were performed. The boundary layer and velocity profiles were measured by the Hot Wire Anemometer (HWA) system and the vortex shedding patterns and flow structures in a wake region were visualized via the Particle Image Velocimetry (PIV) system. Also, it is a measuring on moving ground condition that the experimental values of the critical gap distances, Strouhal numbers and aerodynamic force FFT analyses. Through the experiments, we found that the momentum supply due to moving ground caused the vortex shedding at the lower critical gap distance rather than that of fixed ground. The horizontal and vertical fences increase the critical gap distance and it can suppress the vortex shedding. Consequently, the stability characteristics of the bluff body near a moving ground could be effectively enhanced by the simple passive control such as the vertical fences.

Keywords

Passive flow control;Moving belt experiment;Vortex shedding

References

  1. T. Y. Kim, B. S. Lee, D. H. Lee, , D. H. Lee, A Study on Vortex Shedding Around a Bluff Body Near the Ground, SAE Paper 2003-01-1652., (2003), Detroit.
  2. D.F.G. Durao, P.S.T. Gouveia, J.C.F. Pereira, Velocity characteristics of the flow around a square cross section cylinder placed near a channel wall, Experiments in Fluids, 11, (1991), pp.341-350 https://doi.org/10.1007/BF00211788
  3. Atsushi Okajima, Strohal numbers of Rectangural Cylinders, , J. Fluid Mech.., (1997), pp. 201-237.
  4. Lyn, D. A., Einav, S., Rodi, W., Park, J. H., A Laser-Doppler Velocimetry Study of Ensemble-Averaged Characteristics of the Turbulent near Wake of a Square Cylinder, J. Fluid Mech., 304, (1995), pp. 285-319. https://doi.org/10.1017/S0022112095004435
  5. Bosch, G., Kappler, M., Rodi, W., Experiments on the Flow Past a Square Cylinder Placed near a Wall, Exp. Thermal Fluid Sci., 13, (1996), pp. 292-305. https://doi.org/10.1016/S0894-1777(96)00087-8
  6. Bailey, S. C. C., Kopp, G. A. and Martinuzzi, R. J., Vortex Shedding form a Square Cylinder near a Wall, J. Turbulence, 003, (2003), pp. 1-18.
  7. Martinuzzi, R. J., Bailey, S. C. C, Kopp, G. A. Influence of Wall Proximity on Vortex Shedding from a Square Cylinder, Experiments in Fluids, 34, (2003), pp. 585-596. https://doi.org/10.1007/s00348-003-0594-0
  8. Tamura, T. and Miyagi, T., The effect of Turbulence on Aerodynamic Forces On a Square Cylinder with Various Corner Shapes, J. Wind Eng. Ind. Aerodyn., 83, (1993), pp. 135-145.
  9. Edward G. Duell and A.R. George, Experimental Study of a Ground Vehicle Body Unsteady Near Wake, SAE Paper 1999-01-0812, (1999).
  10. C. K. Choi, Kwon and D. K., Aerodynamic Stability for Square Cylinder with Various Corner Cuts, Wind and Structure, 2(3), (1999), pp. 173-187. https://doi.org/10.12989/was.1999.2.3.173
  11. Khalighi B., S. Zhang and C. Koromilas, Balkanyi, S.R, P. Bernal, G. Laccarino and P. Moin, Experimental and Computational Study of Unsteady Wake Flow Behind a Bluff Body with a Drag Reduction Device, SAE Paper 2001-01-1042, (2001).
  12. B. S. Lee, T. Y. Kim, D. H. Lee, Control of Vortex Shedding behind a Rectangular Cylinder near the Ground, Numerical Heat Transfer, Part A, 47, No 8, (2005), pp. 787-804. https://doi.org/10.1080/10407780590921944
  13. T. Y. Kim, B. S. Lee, D. H. Lee, Study of the Unsteady Wakes Past a Square Cylinder near a Wall, J. Mech. Sci. Tech. 19-5, (2005), pp. 1169-1181. https://doi.org/10.1007/BF02984039
  14. Arnal, M. P., Goering, D. J., Humphrey, J. A. C, Vortex Shedding From a Bluff Body Adjacent to a Plane Sliding Wall, J. Fluid Eng., 113, (1991), pp. 384-398. https://doi.org/10.1115/1.2909508
  15. Sanjay Kumarasamy, Jewel B. Barlow, Computation of unsteady flow over a half-cylinder close to a moving wall, J. Wind Eng. Ind. Aerodyn., 69-71, (1997), pp. 239-248. https://doi.org/10.1016/S0167-6105(97)00158-X
  16. M. S. Kim and Geropp, D., Experimental Investigation of the Ground Effect on the Flow around Some Two-Dimensional Bluff Bodies with Moving-belt Technique, J. Wind Eng. Ind. Aerodyn., 74-76, (1998), pp. 511-519. https://doi.org/10.1016/S0167-6105(98)00046-4
  17. Bhatacharyya, S., Maiti, D. K., Vortex Shedding for Flow over a Square Cylinder Close to a Moving Ground, IUTAM Symposium, New Jergey, USA., (2003).
  18. T. Y. Kim, , B. S. Lee, D. H. Lee, The Enhancement of Aerodynamic Characteristics on Bluff Bodies near a Moving, JSME International Journal, (2006), pp. 787-796. https://doi.org/10.1299/jsmeb.49.787

Acknowledgement

Supported by : Ministry of Land, Infrastructure and Transport of Korean government, National Research Foundation of Korea(NRF)