On shear flow single mode lock-in with both cross-flow and in-line lock-in mechanisms

Marcollo, Hayden; Hinwood, Jonathan Barry

doi:10.1016/j.jfluidstructs.2005.10.001

Cited by 48 publications

(18 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An account of cylinder VIV modelling and experiment studies can be found in a review paper by Gabbai amd Benaroya (2005). Recently, several joint research campaigns have been established to perform the experiment tests on large-scale model risers in realistic uniform/non-uniform flows (Baarholm et al 2006;Chaplin et al 2005;Lie and Kaasen 2006;Marcollo and Hinwood 2006;Tognarelli et al 2004;Trim et al 2005;Vandiver et al 2009). Their main objectives were to gain better insights into the multi-mode VIV responses of long flexible cylinders under different flow conditions, to develop benchmarking data meaningful for the calibration and validation of predictive models and computer codes, and to assess the effectiveness of some VIV suppression devices such as helical strakes.…”

Section: Introductionmentioning

confidence: 99%

Analysis and prediction of vortex-induced vibrations of variable-tension vertical risers in linearly sheared currents

Srinil

2011

Applied Ocean Research

View full text Add to dashboard Cite

Many studies have tackled the problem of vortex-induced vibrations (VIV) of a vertical riser with a constant tension and placed in uniform currents. In this study, attention is focused on the cross-flow VIV modelling, time-domain analysis and prediction of variable-tension vertical risers in linearly sheared currents. The partial-differential equation governing the riser transverse motion is based on a flexural tensioned-beam model with typical pinned-pinned supports. The hydrodynamic excitation model describing the modulation of lift force is based on a distributed van der Pol wake oscillator whose nonlinear equation is also partial-differential due to the implementation of a diffusion term. The variation of empirical wake coefficients with system parameters and the water depth-dependent Reynolds number is introduced. Based on the assumed Fourier mode shape functions obtained by accounting for the effect of nonuniform tension, the Galerkin technique is utilized to construct a low-dimensional multi-mode model governing the coupled fluid-riser interaction system due to VIV. Numerical simulations in the case of varying sheared flow profiles are carried out to systematically evaluate riser nonlinear dynamics and highlight the influence of fluid-structure parameters along with associated VIV aspects. In particular, the effects of shear and tensioned-beam (tension versus bending) parameters are underlined. Some comparisons with published experimental results and observations are qualitatively and quantitatively discussed. Overall parametric analysis and prediction results may be worthwhile for being a new benchmark against future experimental testing and/or numerical results predicted by an alternative model and methodology.

show abstract

Section: Introductionmentioning

confidence: 99%

Analysis and prediction of vortex-induced vibrations of variable-tension vertical risers in linearly sheared currents

Srinil

2011

Applied Ocean Research

View full text Add to dashboard Cite

show abstract

“…can be thought to be 1 in still water [28]. Acceleration transducers with a sensitivity of 1.71 pC/g and a frequency response of 1 Hz-20 kHz were chosen to obtain the displacement signals directly and simultaneously [16,[29][30][31]. The output signal was calibrated to have a linear relationship to the input signal.…”

Section: Experimental Apparatus and Instrumentationmentioning

confidence: 99%

Instability behaviors of a cylinder array under both increasing and decreasing flow velocities

Zhang¹,

Jiang²,

Xiao³

2017

J. vibroeng.

View full text Add to dashboard Cite

Abstract. This study aimed to investigate the effects of increasing and decreasing crossflow velocities on the fluid-elastic instability behaviors of cylinder arrays. The responses of an elastically mounted cylinder in a rigid normal square cylinder array in a water tunnel subjected to crossflow were tested. The responses were simultaneously obtained from both in-line and transverse vibrations. Results show that the responses under increasing freestream velocity differ from those under decreasing freestream velocity. Under decreasing freestream velocity, fluid-elastic instability was accompanied by nonlinear hysteresis, and the cylinder exhibiting this instability can remain in this state for a certain range of flow velocities. Added mass coefficients were also obtained. Two criteria for fluid-elastic instability were applied.

show abstract

“…The data are used to model the fatigue damage of the structures. Long flexible pipelines are investigated also in [18], through an ad hoc designed and built experimental facility: it consists of direct local fluid force measurement at two locations on the cylinder as well as accelerometers spaced along the cylinder axis.…”

Section: Introductionmentioning

confidence: 99%

Diagnosis of vortex induced vibration of a gravity damper

Scappaticci¹,

Castellani²,

Astolfi³

et al. 2018

Diagnostyka

View full text Add to dashboard Cite

A gravity damper is a one-way valve, employed for regulating the airflow rate in ducts, generally constituted by a series of rectangular panels (closure sections), connected to an articulated quadrilateral synchronizing the movements. If the device needs to process large masses of high speed air, as common in the case of energy conversion systems, disadvantageous dynamic effects can occur. In this study, vortexinduced vibration (VIV), occurring on a gravity damper for high values of the Reynolds number, is investigated. The analysis of this work couples numerical methods (Computational Fluid Dynamics with Large-Eddy Simulation turbulence model and Finite Element Method) to experiments: a full-scale accelerometric measurement campaign is actually performed at the wind tunnel facilities of the University of Perugia. VIVs are diagnosed and quantified through the experimental vibration analysis, which is interpreted through numerical simulations. The large amplitude of VIV is interpreted as due to a tendency towards lockin because of the approaching of the vortex shedding frequency to a natural vibration mode of the system. The integrated numerical and experimental framework finally inspires two different design solutions for mitigating the amplitude of VIV: these strategies are tested at the wind tunnel and they are indeed shown to be effective.

show abstract

On shear flow single mode lock-in with both cross-flow and in-line lock-in mechanisms

Cited by 48 publications

References 6 publications

Analysis and prediction of vortex-induced vibrations of variable-tension vertical risers in linearly sheared currents

Analysis and prediction of vortex-induced vibrations of variable-tension vertical risers in linearly sheared currents

Instability behaviors of a cylinder array under both increasing and decreasing flow velocities

Diagnosis of vortex induced vibration of a gravity damper

Contact Info

Product

Resources

About