Abstract
Large-amplitude self-induced aerodynamic vibrations of bluff cylinders are perhaps explained by the unsteady aerodynamic forces determined by the relative angle of attack and the time derivative of it in comparatively higher reduced wind velocity region. The authors have obtained this aerodynamic force by measuring the aerodynamic force of continuously rotating body, and have shown that the torsional 1DOF (degree-of-freedom) vibration can be explained. In this study, the validity and range of the vertical 1DOF vibration that can be expressed by the aerodynamic force of continuously rotating body were investigated using a rectangular section with a side ratio B/D = 2, from high to low reduced wind velocity region. As a result, the validity was shown in the high reduced wind velocity region and the large amplitude region of the low reduced wind velocity region. It was also shown that even in the low reduced wind velocity and small amplitude region, the aerodynamic characteristics during vertical 1DOF vibration can be explained by the relative angle of attack and the time derivative of it.
