Characterisitcs of coupled aerodynamic forces of a galloping cylinder with D-section

作者：Ma, Wen-Yong; Deng, Ran-Ran; Lu, Jin-Yu

来源：Journal of Vibration Engineering, 2017, 30(5): 755-763.

DOI：10.16385/j.cnki.issn.1004-4523.2017.05.008

• Aerodynamic forces
• Coupled aerodynamics
• Critical wind speed
• Galloping instabilities
• Galloping response
• Generation mechanism
• Single degree of freedoms
• Wind tunnel tests

The coupled aerodynamic forces on a galloping cylinder can reveal the generation mechanism of galloping and provide a measure of developing galloping suppression. A cylinder with D-section, which has been used to simulate the shape of the iced conductor, is tested in wind tunnel to obtain the static aerodynamic forces, galloping response and coupled aerodynamic forces. The characteristics of the aerodynamic forces are illustrated. The across-wind single-degree-of-freedom galloping instability and critical wind speed are estimated based on the quasi-steady assumption. By analyzing the galloping responses and coupled aerodynamic forces, a coupled aerodynamic force variation process is revealed. The result shows that the galloping more likely occurs when the angle between the wind direction and the line side of the D-section is around 40°. This vibration is induced by the variation of the separation state with the angle of attack. The responses are mainly contributed by the wind pressure on the region behind the separation points. This reveals that galloping is a wake flow induced vibration and the sensitivity of the vibration on separation points make a possibility on suppressing the galloping response by controlling the separation points.

• 出版日期2017
• 单位石家庄铁道大学