Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-25T13:27:47.501Z Has data issue: false hasContentIssue false

Interaction of Oscillatory Flows with a Square Cylinder

Published online by Cambridge University Press:  05 May 2011

M.-J. Chern*
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 10607, R.O.C.
Y.-J. Lu*
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 10607, R.O.C.
S.-C. Chang*
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 10607, R.O.C.
I.-C. Cheng*
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 10607, R.O.C.
*
*Associate Professor
**Postgraduate student
**Postgraduate student
**Postgraduate student
Get access

Abstract

The behaviour of vortices induced by a single square cylinder in an oscillating flow was investigated. The flow patterns in the vicinity of square cylinders were visualized using an in-house numerical model. Meanwhile, force coefficients exerted on the square cylinder were determined numerically. In terms of various Keulegan-Carpenter (KC) numbers, it turns out that the flow patterns for an oscillating flow past a single cylinder can be divided into three modes: (i) no vortex, (ii) pairs of symmetric vortices, and (iii) asymmetric vortex shedding. Reynolds (Re) number did not affect the flow field apparently in this study. In addition, the in-line force coefficient decreases exponentially as KC increases. Spectrum analysis of in-line force coefficients for various KCs was provided. It can be found that the flow system was at a periodic state at small KC for the first two modes. Variations of the flow system from a periodic state to a highly nonlinear state in which asymmetric vortex shedding appeared were demonstrated for increasing KC. The relationship between the in-line force and KC was provided for future applications.

Type
Technical Note
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Williamson, C. H. K., “Sinusoidal Flow Relative to Circular Cylinders,” Journal of Fluid Mechanics, 155, pp. 141174 (1985).CrossRefGoogle Scholar
2.Williamson, C. H. K. and Roshko, A., “Vortex Formation in the Wake of Oscillating Cylinder,” Journal of Fluids and Structures, 2, pp. 355381 (1985).Google Scholar
3.Obasaju, E. D., Bearman, P. W. and Graham, J. M. R., “A Study of Forces, Circulation and Vortex Patterns around a Circular Cylinder in Oscillating Flow,” Journal of Fluid Mechanics, 196, pp. 467494 (1988).Google Scholar
4.Sumer, B. M. and Fredsoe, J., Hydrodynamics around Cylindrical Structures, World Scientific Publish Co., Singapore (1997).Google Scholar
5.Sarpkaya, T., “Force on a Circular Cylinder in Viscous Oscillating Flow at Low Keulegan-Carpenter Numbers,” Journal of Fluid Mechanics, 165, pp. 6171 (1986).Google Scholar
6.Honji, H., “Streaked Flow around an Oscillating Circular Cylinder,” Journal of Fluid Mechanics, 107, pp. 509520 (1981).CrossRefGoogle Scholar
7.Bearman, P. W., Graham, J. M. R., Obasaju, E. D. and Drossopulos, G. M., “The Influence of Corner Radius on the Forces Experienced by Cylindrical Bluff Bodies in Oscillatory Flow,” Applied Ocean Research, 6, pp. 8389 (1984).CrossRefGoogle Scholar
8.Zheng, W. and Dalton, C., “Numerical Prediction of Force on Rectangular Cylinders in Oscillating Viscous Flow,” Journal of Fluids and Structures, 13, pp. 225249 (1999).CrossRefGoogle Scholar
9.Leonard, B. P., “A Stable and Accurate Convective Modeling Procedure Based on Quadratic Upstream Interpolation,” Computer Methods in Applied Mechanics and Engineering, 19, pp. 5998 (1979).CrossRefGoogle Scholar
10.Hirt, C. W., Nichols, B. D. and Romero, N. C., “SOLA— A Numerical Solution Algorithm for Transient Fluid Flow,” LA-5852 Technical Report: Los Alamos Scientific Laboratory, USA (1975).CrossRefGoogle Scholar