## Aerodynamic damping of nonlinear movement of conductor cables in laminar and turbulent wind flow

- It is widely accepted that aerodynamic damping is a decisive parameter influencing the dynamic response of overhead transmission line conductors in turbulent wind flow. But anyway, methods of how to account for the effects of aerodynamic damping differ significantly and so might do the results. In this work, the source of aerodynamic damping shall be revised leading to the well-known formulation for a linear pendulum being the result of the relative velocity between the structure and wind flow. Based on wind tunnel tests and validated by simulations, the differences to a pendulum movement of a sagging cable are shown. The reasons for that deviation are the large deflections, resulting in a movement non parallel to the acting wind flow. For some analysis, in particular those in frequency domain, it is practically not possible to incorporate aerodynamic damping implicitly by fluid structure interaction. If the dynamic movement can be linearized at a working point of the mean deflection,It is widely accepted that aerodynamic damping is a decisive parameter influencing the dynamic response of overhead transmission line conductors in turbulent wind flow. But anyway, methods of how to account for the effects of aerodynamic damping differ significantly and so might do the results. In this work, the source of aerodynamic damping shall be revised leading to the well-known formulation for a linear pendulum being the result of the relative velocity between the structure and wind flow. Based on wind tunnel tests and validated by simulations, the differences to a pendulum movement of a sagging cable are shown. The reasons for that deviation are the large deflections, resulting in a movement non parallel to the acting wind flow. For some analysis, in particular those in frequency domain, it is practically not possible to incorporate aerodynamic damping implicitly by fluid structure interaction. If the dynamic movement can be linearized at a working point of the mean deflection, a modification to the linear approach is suggested. This approach is validated by simulation with a finite element model of an existing overhead transmission line, calibrated with onsite measurements for wind velocities at lower levels. Further accent is put on the different possibilities to incorporate aerodynamic damping in time step analysis, such as Rayleigh damping or modal damping. The differences between both approaches are emphasized and modal damping is shown to be the most adequate representation of aerodynamic damping.…

Autoren/innen: | Dominik Stengel, K. Thiele, M. Clobes, Milad Mehdianpour |
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Dokumenttyp: | Beitrag zu einem Tagungsband |

Veröffentlichungsform: | Verlagsliteratur |

Sprache: | Englisch |

Titel des übergeordneten Werkes (Englisch): | ICWE14 - 14th International conference on wind engineering |

Jahr der Erstveröffentlichung: | 2015 |

Organisationseinheit der BAM: | 7 Bauwerkssicherheit |

7 Bauwerkssicherheit / 7.2 Ingenieurbau | |

Herausgeber (Institution): | International Association for Wind Engineering |

Erste Seite: | 1 |

Letzte Seite: | 9 |

Freie Schlagwörter: | Aerodynamic damping; Conductor cables; Nonlinear finite element simulation; Overhead transmission lines; Wind tunnel experiments |

Veranstaltung: | ICWE14 - 14th International conference on wind engineering |

Veranstaltungsort: | Porto Alegre, Brazil |

Beginndatum der Veranstaltung: | 21.06.2015 |

Enddatum der Veranstaltung: | 26.06.2015 |

ISBN: | 978-85-66094-07-7 |

Verfügbarkeit des Volltexts: | Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access") |

Datum der Freischaltung: | 20.02.2016 |

Referierte Publikation: | Nein |