Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-12-01T00:55:08.172Z Has data issue: false hasContentIssue false

The motion of a 2D pendulum in a channel subjected to an incoming flow

Published online by Cambridge University Press:  22 December 2014

Andrea Fani*
Affiliation:
Laboratory of Fluid Mechanics and Instabilities, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
François Gallaire
Affiliation:
Laboratory of Fluid Mechanics and Instabilities, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
*
Email address for correspondence: [email protected]

Abstract

The flow around a tethered cylinder subjected to an incoming flow transverse to its main axis and confined in a channel is investigated by means of global stability analysis of the full coupled body–fluid problem. When the cylinder is strongly confined (ratio of cylinder diameter to cell height, $D/H=0.66$) we retrieve the confinement-induced instability (CIV) discovered by Semin et al. (J. Fluid Mech., vol. 690, 2011, pp. 345–365), which sets in at a Reynolds number below the vortex-induced vibration threshold. For a moderately confined case ($D/H=0.3$), a new steady static instability is discovered, referred to as confinement-induced divergence (CID). This instability saturates into an asymmetric steady solution through a supercritical pitchfork bifurcation. In addition, the CIV and CID instabilities are studied via a reduced model obtained by considering a quasi-static response of the fluid, allowing for tracing back the physical mechanisms responsible for the instabilities.

Type
Papers
Copyright
© 2014 Cambridge University Press 

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

Assemat, P., Fabre, D. & Magnaudet, J. 2011 The onset of unsteadiness of two-dimensional bodies falling or rising freely in a viscous fluid: a linear study. J. Fluid Mech. 690, 173202.CrossRefGoogle Scholar
Bandi, M. M., Concha, A., Wood, R. & Mahadevan, L. 2013 A pendulum in a flowing soap film. Phys. Fluids 25 (4), 041702.CrossRefGoogle Scholar
Biancofiore, L., Gallaire, F. & Pasquetti, R. 2011 Influence of confinement on a two-dimensional wake. J. Fluid Mech. 688, 297320.CrossRefGoogle Scholar
Bolster, D., Hershberger, R. E. & Donnelly, R. J. 2010 Oscillating pendulum decay by emission of vortex rings. Phys. Rev. E 81 (4), 046317.CrossRefGoogle ScholarPubMed
Camarri, S. & Giannetti, F. 2007 On the inversion of the von Kármán street in the wake of a confined square cylinder. J. Fluid Mech. 574, 169178.CrossRefGoogle Scholar
Chen, J.-H., Pritchard, W. G. & Tavener, S. J. 1995 Bifurcation for flow past a cylinder between parallel planes. J. Fluid Mech. 284, 2341.CrossRefGoogle Scholar
Cossu, C. & Morino, L. 2000 On the instabiliry of a spring-mounted circular cylinder in a viscous flow at low Reynolds numbers. J. Fluids Struct. 14, 183196.CrossRefGoogle Scholar
Fabre, D., Assemat, P. & Magnaudet, J. 2011 A quasi-static approach to the stability of the path of heavy bodies falling within a viscous fluid. J. Fluids Struct. 27 (5–6), 758767.CrossRefGoogle Scholar
Fabre, D., Auguste, F. & Magnaudet, J. 2008 Bifurcations and symmetry breaking in the wake of axisymmetric bodies. Phys. Fluids 20 (5), 051702.CrossRefGoogle Scholar
Fani, A., Camarri, S. & Salvetti, M. V. 2012 Stability analysis and control of the flow in a symmetric channel with a sudden expansion. Phys. Fluids 24 (8), 084102.CrossRefGoogle Scholar
Govardhan, R. N. & Williamson, C. H. K. 2005 Vortex-induced vibrations of a sphere. J. Fluid Mech. 531, 1147.CrossRefGoogle Scholar
Happel, J. & Brenner, H. 1983 Low Reynolds Number Hydrodynamics: with Special Applications to Particulate Media, Vol. 1. Springer.CrossRefGoogle Scholar
Hecht, F. 2012 New development in Freefem $++$ . J. Numer. Math. 20 (3–4), 251265.CrossRefGoogle Scholar
Lehoucq, R. B., Sorensen, D. C. & Yang, C. 1998 ARPACK Users’ Guide: Solution of Large-Scale Eigenvalue Problems with Implicitly Restarted Arnoldi Methods, Vol. 6. SIAM.CrossRefGoogle Scholar
Meis, M., Varas, F., Velázquez, A. & Vega, J. M. 2010 Heat transfer enhancement in micro-channels caused by vortex promoters. Intl J. Heat Mass Transfer 53 (1–3), 2940.CrossRefGoogle Scholar
Meliga, P., Chomaz, J.-M. & Sipp, D. 2009 Global mode interaction and pattern selection in the wake of a disk: a weakly nonlinear expansion. J. Fluid Mech. 633, 159189.CrossRefGoogle Scholar
Meliga, P., Sipp, D. & Chomaz, J. 2010 Open-loop control of compressible afterbody flows using adjoint methods. Phys. Fluids 22 (5), 118.CrossRefGoogle Scholar
Mittal, S. & Singh, S. 2005 Vortex-induced vibrations at subcritical $\mathit{Re}$ . J. Fluid Mech. 534, 185194.CrossRefGoogle Scholar
Nakabayashi, K., Yoshida, N. & Aoi, T. 1993 Numerical analysis for viscous shear flows past a circular cylinder at intermediate reynolds numbers. JSME Intl J. Ser. B, Fluids Therm. Engng 36 (1), 3441.CrossRefGoogle Scholar
Obligado, M., Puy, M. & Bourgoin, M. 2013 Bi-stability of a pendular disk in laminar and turbulent flows. J. Fluid Mech. 728, R2, doi:10.1017/jfm.2013.312.CrossRefGoogle Scholar
Ryan, K., Pregnalato, C. J., Thompson, M. C. & Hourigan, K. 2004 Flow-induced vibrations of a tethered circular cylinder. J. Fluids Struct. 19 (8), 10851102.CrossRefGoogle Scholar
Sahin, M. & Owens, R. G. 2004 A numerical investigation of wall effects up to high blockage ratios on two-dimensional flow past a confined circular cylinder. Phys. Fluids 16 (5), 13051320.CrossRefGoogle Scholar
Sanchez-Sanz, M., Fernandez, B. & Velazquez, A. 2009 Energy-harvesting microresonator based on the forces generated by the Kármán street around a rectangular prism. J. Microelectromech. Syst. 18 (2), 449457.CrossRefGoogle Scholar
Semin, B., Decoene, A., Hulin, J.-P., François, M. L. M. & Auradou, H. 2011 New oscillatory instability of a confined cylinder in a flow below the vortex shedding threshold. J. Fluid Mech. 690, 345365.CrossRefGoogle Scholar
Taylor, C. & Hood, P. 1973 A numerical solution of the Navier–Stokes equations using the finite element technique. Comput. Fluids 1 (1), 73100.CrossRefGoogle Scholar
Williamson, C. H. K. & Govardhan, R. 2004 Vortex-induced vibrations. Annu. Rev. Fluid Mech. 36 (1), 413455.CrossRefGoogle Scholar
Zovatto, L. & Pedrizzetti, G. 2001 Flow about a circular cylinder between parallel walls. J.  Fluid Mech. 440, 125.CrossRefGoogle Scholar