Galloping instabilities of two-dimensional triangular cross-section bodies

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 degrees. The results have been summarized in a stability map, where galloping instability zones in the angle of attack-main vertex angle plane-are identified.