Galloping Mechanism of a Closely Tuned 3-DOF System Considering Aerodynamic Stiffness

• DOI: 10.1061/jsendh.steng-11829
• Publication Date: 2023-01-30T10:48:37Z
• Authors: Zuopeng Wen; Wenjuan Lou; Jiang Yu; Haiwei Xu
• Keywords: Aerodynamic force; Aeroelasticity

The galloping problem of a three-degree-of-freedom (3-DOF) system with strongly coupled vertical-horizontal-torsional motions has drawn wide attention due to the high risk and subsequent serious damages caused, but mechanism remains unclear because complex interaction structural motion aerodynamic forces. In present work, 3-DOF close frequencies in three directions was analyzed reveal under motion. Based on quasi-steady theory, theoretical models single section multiple subsections were studied by using perturbation method based order analysis, stability criterion considering stiffness small-frequency detuning established. This reveals promoting initiation. Galloping tests segmental model an eight-bundled conductor D-shaped ice accretion conducted examine validity proposed various wind conditions. For tests, able trigger even positive damping all directions, which could be explained criterion. Numerical examples also employed validate attack angles 0°–180°. numerical study showed that can promote regardless angles, especially speeds. results initiated provide new insight into prediction galloping.