Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-28T08:51:38.572Z Has data issue: false hasContentIssue false

A freely yawing axisymmetric bluff body controlled by near-wake flow coupling

Published online by Cambridge University Press:  29 January 2019

Thomas J. Lambert
Affiliation:
Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405, USA
Bojan Vukasinovic*
Affiliation:
Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405, USA
Ari Glezer
Affiliation:
Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405, USA
*
Email address for correspondence: [email protected]

Abstract

Flow-induced oscillations of a wire-mounted, freely yawing axisymmetric round bluff body and the induced loads are regulated in wind tunnel experiments (Reynolds number $60\,000<Re_{D}<200\,000$) by altering the reciprocal coupling between the body and its near wake. This coupling is controlled by exploiting the receptivity of the azimuthal separating shear layer at the body’s aft end to controlled pulsed perturbations effected by two diametrically opposed and independently controlled aft-facing rectangular synthetic jets. The model is supported by a thin vertical wire upstream of its centre of pressure, and prescribed modification of the time-dependent flow-induced loads enables active control of its yaw attitude. The dynamics of the interactions and coupling between the actuation and the cross-flow are investigated using simultaneous, time-resolved measurements of the body’s position and phase-locked particle image velocimetry measurements in the yawing plane. It is shown that the interactions between trains of small-scale actuation vortices and the local segment of the aft-separating azimuthal shear layer lead to partial attachment, and the ensuing asymmetric modifications of the near-wake vorticity field occur within 15 actuation cycles (approximately three convective time scales), which is in agreement with measurements of the flow loads in an earlier study. Open- and closed-loop actuation can be coupled to the natural, unstable motion of the body and thereby affect desired attitude control within 100 convective time scales, as is demonstrated by suppression or enhancement of the lateral motion.

Type
JFM Papers
Copyright
© 2019 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

Amitay, M. & Glezer, A. 2006 Flow transients induced on a 2D airfoil by pulse-modulated actuation. Exp. Fluids 40, 329331.10.1007/s00348-005-0069-6Google Scholar
Bisplinghoff, R. L., Ashley, H. & Halfman, R. L. 1996 Aeroelasticity. Dover.Google Scholar
Blevins, R. D. 1990 Flow-Induced Vibration. Van Nostrand Reinhold Company.Google Scholar
Carberry, J. & Sheridan, J. 2007 Wake states of a tethered cylinder. J. Fluid Mech. 592, 121.10.1017/S0022112007007707Google Scholar
Chen, W. L., Xin, D. B., Xu, F., Li, H., Ou, J. P. & Hu, H. 2013 Suppression of vortex-induced vibration of a circular cylinder using suction-based flow control. J. Fluids Struct. 42, 2539.10.1016/j.jfluidstructs.2013.05.009Google Scholar
Every, M. J., King, R. & Weaver, D. S. 1982 Vortex-excited vibrations of cylinders and cables and their suppression. Ocean Engng 9, 135157.10.1016/0029-8018(82)90010-5Google Scholar
Feng, C. C.1968 The measurement of vortex induced effects in flow past stationary and oscillating circular and D-section cylinders. Master’s thesis, University of British Columbia, Vancouver, Canada.Google Scholar
Flemming, F. & Williamson, C. H. K. 2005 Vortex-induced vibrations of a pivoted cylinder. J. Fluid Mech. 522, 215252.10.1017/S0022112004001831Google Scholar
Fung, Y. C. 1969 An Introduction to the Theory of Aeroelasticity. Dover.Google Scholar
Glezer, A. & Amitay, M. 2002 Synthetic jets. Annu. Rev. Fluid Mech. 24, 503529.10.1146/annurev.fluid.34.090501.094913Google Scholar
Govardhan, R. & Williamson, C. H. K. 2002 Resonance forever: existence of a critical mass and an infinite regime of resonance in vortex-induced vibration. J. Fluid Mech. 473, 147166.10.1017/S0022112002002318Google Scholar
Goyta, S., Mueller-Vahl, H. & Greenblatt, D. 2013 Tethered cube stabilization by means of leading-edge DBD plasma actuation. Exp. Fluids 54, 116.10.1007/s00348-012-1446-6Google Scholar
Griffin, O. M. & Ramberg, S. E. 1982 Some recent studies of vortex shedding with application to marine tubulars and risers. J. Energy Resour. Technol. 104, 213.10.1115/1.3230377Google Scholar
Lambert, T. J.2016 Aerodynamic control of flow dynamics coupled to a free-flight axisymmetric body. PhD dissertation, Georgia Institute of Technology.Google Scholar
Lambert, T. J., Vukasinovic, B. & Glezer, A. 2015 Active decoupling of the axisymmetric body wake response to a pitching motion. J. Fluids Struct. 59, 129145.10.1016/j.jfluidstructs.2015.08.017Google Scholar
Parkinson, G. V. 1971 Wind-induced instability of structures. Phil. Trans. A Math. Phys. Eng. Sci. 269, 395413.10.1098/rsta.1971.0040Google Scholar
Parkinson, G. 1989 Phenomena and modelling of flow-induced vibrations of bluff bodies. Prog. Aerosp. Sci. 26, 169224.10.1016/0376-0421(89)90008-0Google Scholar
Ploumhans, P., Winckelmans, G. S., Salmon, J. K., Leonard, A. & Warren, M. S. 2002 Vortex methods for direct numerical simulation of three-dimensional bluff body flows: application to the sphere at Re = 300, 500, and 1000. J. Comput. Phys. 178, 427463.10.1006/jcph.2002.7035Google Scholar
Rinehart, C. S.2011 Aerodynamic forces induced by controlled transitory flow on a body of revolution. PhD thesis, Georgia Institute of Technology.Google Scholar
Rival, D. & Tropea, C. 2010 Characteristics of pitching and plunging airfoils under dynamic-stall conditions. J. Aircraft 47, 8086.10.2514/1.42528Google Scholar
Ryan, K., Pregnalato, C. J., Thompson, M. C. & Hourigan, K. 2004 Flow-induced vibrations of a tethered circular cylinder. J. Fluids Struct. 19, 10851102.10.1016/j.jfluidstructs.2004.07.005Google Scholar
Sarioglu, M., Akansu, Y. E. & Yavuz, T. 2005 Control of the flow around square cylinders at incidence by using a rod. AIAA J. 43, 14191426.10.2514/1.9460Google Scholar
van Hout, R., Katz, A. & Greenblatt, D. 2013 Acoustic control of vortex-induced vibrations of a tethered sphere. AIAA J. 51, 754757.10.2514/1.J052086Google Scholar
Vukasinovic, B. & Glezer, A.2006 Transitory fluidic control of turbulent shear flows. AIAA Paper 2006-3227.Google Scholar
Williamson, C. H. K. & Govardhan, R. 2004 Vortex-induced vibrations. Annu. Rev. Fluid Mech. 36, 413455.10.1146/annurev.fluid.36.050802.122128Google Scholar
Williamson, C. H. K. & Roshko, A. 1988 Vortex formation in the wake of an oscillating cylinder. J. Fluids Struct. 2, 355381.10.1016/S0889-9746(88)90058-8Google Scholar
Zdravkovich, M. M. 1981 Review and classification of various aerodynamic and hydrodynamic means for suppressing vortex shedding. J. Wind Engng Ind. Aerodyn. 7, 145189.10.1016/0167-6105(81)90036-2Google Scholar