Galloping instabilities of two-dimensional triangular cross-section bodies
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Galloping is a type of aeroelastic instability characterized by large amplitude, low frequency, normal to wind oscillations. It normally appears in bodies with small stiffness and structural damping when they are placed in a flow and the incident velocity is high enough. In this paper a systematic approach for the analysis of galloping of triangular cross-section bodies is reported. Wind tunnel experiments have been conducted aiming at establishing the unstable characteristics of isosceles triangular cross-section bodies when subjected to a uniform flow with angles of attack ranging from 0 to 180°. The results have been summarized in a stability map, where galloping instability zones in the angle of attack—main vertex angle plane—are identified.
KeywordsWind Tunnel Aerodynamic Force Lift Coefficient Instability Region Wind Flow
The authors thank J. Fernández, V. Pinilla, J.M. Rey and G. Vidal for their helpful contribution in performing the experiments. The authors also thank the reviewers of this paper for their valuable comments.
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