Validation of the Small Boundary Displacement Model of Fluid-Structure Coupling for Predicting Fluid-Elastic Lock-In

Volume 4: Fluid Structure Interaction ◽

10.1115/pvp2005-71570 ◽

2005 ◽

Author(s):

David J. Manko ◽

M. M. Sussman

Keyword(s):

Coupling Model ◽

Elastic Response ◽

Small Displacement ◽

Two Dimensional ◽

Fluid Structure ◽

Boundary Displacement ◽

Displacement Theory ◽

Lock In ◽

Displacement Model ◽

Structural Motion

This paper describes the validation of the Small Boundary Displacement Model (SBDM) of fluid-structure coupling for predicting fluid-elastic lock-in response of a D-shaped cylinder in crossflow. This coupling model extends structural small displacement theory to fluid-structure interfaces, eliminating the need for temporally changing meshes when structural motion is small compared with problem dimensions. The SBDM algorithm accurately predicts the range and characteristics of lock-in behavior when compared to an independent two-dimensional numerical solution. Further validation of the SBDM simulations is provided by comparisons to fluid-only solutions at the limits of lock-in where the cylinder boundary is forced to oscillate at the same amplitudes as the corresponding coupled simulations. The SBDM predicted fluid-elastic response exceeds the 20 dB limit commonly used for experimentally identifying lock-in behavior.

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Predicting Oscillatory Fluid-Elastic Instability of a Tongue-in-Groove Leakage Joint

Journal of Applied Mechanics ◽

10.1115/1.1640368 ◽

2004 ◽

Vol 71 (1) ◽

pp. 41-48

Author(s):

David J. Manko ◽

Myron M. Sussman

Keyword(s):

Coupling Model ◽

Elastic Stability ◽

Small Displacement ◽

Elastic Instability ◽

Fluid Structure ◽

Boundary Displacement ◽

Tongue In Groove ◽

Displacement Theory ◽

Displacement Model ◽

Structural Motion

This paper describes the application of the small boundary displacement model (SBDM) of fluid-structure coupling for predicting oscillatory fluid-elastic instability of a tongue-in-groove leakage joint. This coupling model extends structural small displacement theory to fluid-structure interfaces, eliminating the need for temporally changing meshes when structural motion is small compared with joint dimensions. The SBDM algorithm accurately predicts the onset of oscillatory instability for a tongue-in-groove leakage joint when compared with experimental data. Even though the methodology is specifically applied to a tongue-in-groove joint, the approach is equally suitable for evaluating the fluid-elastic stability of leakage joints in general.

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Nonlinear Dynamics of a Fluid–Structure Coupling Model for Vortex-Induced Vibration

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455419500718 ◽

2019 ◽

Vol 19 (07) ◽

pp. 1950071 ◽

Cited By ~ 5

Author(s):

Jie Chen ◽

Qiu-Sheng Li

Keyword(s):

Vortex Shedding ◽

Multiple Scales ◽

Coupled Model ◽

Coupling Model ◽

Motion Equation ◽

Multiple Scales Method ◽

Modulation Equation ◽

Fluid Structure ◽

Vortex Induced Vibration ◽

Lock In

This paper presents a fluid–structure coupling model to investigate the vortex-induced vibration of a circular cylinder subjected to a uniform cross-flow. A modified van der Pol nonlinear equation is employed to represent the fluctuating nature of vortex shedding. The wake oscillator is coupled with the motion equation of the cylinder by applying coupling terms in modeling the fluid–structure interaction. The transient responses of the fluid–structure coupled model are presented and discussed by numerical simulations. The results demonstrate the main features of the vortex-induced vibration, such as lock-in phenomenon, i.e. resonant oscillation of the cylinder occurs when the vortex shedding frequency is near to the natural frequency of the cylinder. The resonant responses of the fluid–structure coupled model in the lock-in region are determined by the multiple scales method. The accuracy of the asymptotic solution by the multiple scales method is verified by comparing with the numerical solution from the motion equation. The effects of different parameters on the steady state amplitude of oscillation are investigated for a given set of parameters. Frequency–response curves obtained from the modulation equation demonstrate the existence of jump phenomena.

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A simplified numerical and analytical study for assessing the seismic response of a gravity concrete lock

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952021000100004 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Neander Berto Mendes ◽

Lineu José Pedroso ◽

Paulo Marcelo Vieira Ribeiro

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Analytical Study ◽

Two Dimensional ◽

The Finite Element Method ◽

Fluid Structure ◽

Analytical Formulation ◽

Acoustic Cavity ◽

Water Chamber ◽

Structure Problem

ABSTRACT: This work presents the dynamic response of a lock subjected to the horizontal S0E component of the El Centro earthquake for empty and completely filled water chamber cases, by coupled fluid-structure analysis. Initially, the lock was studied by approximation, considering it similar to the case of a double piston coupled to a two-dimensional acoustic cavity (tank), representing a simplified analytical model of the fluid-structure problem. This analytical formulation can be compared with numerical results, in order to qualify the responses of the ultimate problem to be investigated. In all the analyses performed, modeling and numerical simulations were done using the finite element method (FEM), supported by the commercial software ANSYS.

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Fluid-Structure Energy Transfer of a Tensioned Beam Subject to Vortex-Induced Vibrations in Shear Flow

Volume 7: CFD and VIV; Offshore Geotechnics ◽

10.1115/omae2011-49057 ◽

2011 ◽

Author(s):

Remi Bourguet ◽

Michael S. Triantafyllou ◽

Michael Tognarelli ◽

Pierre Beynet

Keyword(s):

Energy Transfer ◽

Shear Flow ◽

Cross Flow ◽

Reynolds Numbers ◽

Structural Vibrations ◽

Fluid Structure ◽

Vortex Induced Vibrations ◽

Linear Shear ◽

Structural Responses ◽

Lock In

The fluid-structure energy transfer of a tensioned beam of length to diameter ratio 200, subject to vortex-induced vibrations in linear shear flow, is investigated by means of direct numerical simulation at three Reynolds numbers, from 110 to 1,100. In both the in-line and cross-flow directions, the high-wavenumber structural responses are characterized by mixed standing-traveling wave patterns. The spanwise zones where the flow provides energy to excite the structural vibrations are located mainly within the region of high current where the lock-in condition is established, i.e. where vortex shedding and cross-flow vibration frequencies coincide. However, the energy input is not uniform across the entire lock-in region. This can be related to observed changes from counterclockwise to clockwise structural orbits. The energy transfer is also impacted by the possible occurrence of multi-frequency vibrations.

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