### Abstract

Flutter instability is a typical aerodynamic vibration phenomenon of slender elastic bridges. The sensitivity for flutter can be predicted by determining the so-called nutter derivatives from the small-scale model of the bridge. This work investigates an elastic supported two d.o.f. bridge section model which can move vertically and rotate around a horizontal axis. These movements correspond to the bending and torsional vibrations of the bridge. The linearised equations of motion is assumed to be known, thus, the aerodynamic forces can be determined from wind-tunnel experiments. These forces are assumed as linear functions of the generalised coordinates and their time-derivatives. The coefficients of the linear terms called also as flutter derivatives depend on the flow (wind) velocity. These coefficients are to be determined by the Monte Carlo method using the measured acceleration data. The obtained results are compared to the results determined by curve-fitting on the acceleration time-signal. The original (structural) damping and stiffness matrices can be modified by using the flutter derivatives since the equations of motion form a homogeneous linear differential equation system. Thus, we get effective damping and stiffness matrices. Flutter instability occurs when a harmonic solution satisfies the equations. The critical flow velocity which the system loses its stability at is also compared to the stability boundary of the analytical model based on Theodorsen's approach.

Original language | English |
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Title of host publication | 21st International Congress on Sound and Vibration 2014, ICSV 2014 |

Publisher | International Institute of Acoustics and Vibrations |

Pages | 2663-2670 |

Number of pages | 8 |

Volume | 3 |

ISBN (Print) | 9781634392389 |

Publication status | Published - 2014 |

Event | 21st International Congress on Sound and Vibration 2014, ICSV 2014 - Beijing, China Duration: Jul 13 2014 → Jul 17 2014 |

### Other

Other | 21st International Congress on Sound and Vibration 2014, ICSV 2014 |
---|---|

Country | China |

City | Beijing |

Period | 7/13/14 → 7/17/14 |

### Fingerprint

### ASJC Scopus subject areas

- Acoustics and Ultrasonics

### Cite this

*21st International Congress on Sound and Vibration 2014, ICSV 2014*(Vol. 3, pp. 2663-2670). International Institute of Acoustics and Vibrations.

**Experimental and analytical investigation of a fluttering bridge section model.** / Szabó, Zsolt; Stépán, G.; Zelei, Ambrus.

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

*21st International Congress on Sound and Vibration 2014, ICSV 2014.*vol. 3, International Institute of Acoustics and Vibrations, pp. 2663-2670, 21st International Congress on Sound and Vibration 2014, ICSV 2014, Beijing, China, 7/13/14.

}

TY - GEN

T1 - Experimental and analytical investigation of a fluttering bridge section model

AU - Szabó, Zsolt

AU - Stépán, G.

AU - Zelei, Ambrus

PY - 2014

Y1 - 2014

N2 - Flutter instability is a typical aerodynamic vibration phenomenon of slender elastic bridges. The sensitivity for flutter can be predicted by determining the so-called nutter derivatives from the small-scale model of the bridge. This work investigates an elastic supported two d.o.f. bridge section model which can move vertically and rotate around a horizontal axis. These movements correspond to the bending and torsional vibrations of the bridge. The linearised equations of motion is assumed to be known, thus, the aerodynamic forces can be determined from wind-tunnel experiments. These forces are assumed as linear functions of the generalised coordinates and their time-derivatives. The coefficients of the linear terms called also as flutter derivatives depend on the flow (wind) velocity. These coefficients are to be determined by the Monte Carlo method using the measured acceleration data. The obtained results are compared to the results determined by curve-fitting on the acceleration time-signal. The original (structural) damping and stiffness matrices can be modified by using the flutter derivatives since the equations of motion form a homogeneous linear differential equation system. Thus, we get effective damping and stiffness matrices. Flutter instability occurs when a harmonic solution satisfies the equations. The critical flow velocity which the system loses its stability at is also compared to the stability boundary of the analytical model based on Theodorsen's approach.

AB - Flutter instability is a typical aerodynamic vibration phenomenon of slender elastic bridges. The sensitivity for flutter can be predicted by determining the so-called nutter derivatives from the small-scale model of the bridge. This work investigates an elastic supported two d.o.f. bridge section model which can move vertically and rotate around a horizontal axis. These movements correspond to the bending and torsional vibrations of the bridge. The linearised equations of motion is assumed to be known, thus, the aerodynamic forces can be determined from wind-tunnel experiments. These forces are assumed as linear functions of the generalised coordinates and their time-derivatives. The coefficients of the linear terms called also as flutter derivatives depend on the flow (wind) velocity. These coefficients are to be determined by the Monte Carlo method using the measured acceleration data. The obtained results are compared to the results determined by curve-fitting on the acceleration time-signal. The original (structural) damping and stiffness matrices can be modified by using the flutter derivatives since the equations of motion form a homogeneous linear differential equation system. Thus, we get effective damping and stiffness matrices. Flutter instability occurs when a harmonic solution satisfies the equations. The critical flow velocity which the system loses its stability at is also compared to the stability boundary of the analytical model based on Theodorsen's approach.

UR - http://www.scopus.com/inward/record.url?scp=84922636473&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84922636473&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:84922636473

SN - 9781634392389

VL - 3

SP - 2663

EP - 2670

BT - 21st International Congress on Sound and Vibration 2014, ICSV 2014

PB - International Institute of Acoustics and Vibrations

ER -