Full-scale measurement of wind pressure on the surface of an oscillating circular cylinders

Under wind excitation, many slender structural members with circular cross sections have exhibited large-amplitude vibrations. The nature of some problematic vibrations remains to be fully understood. To investigate the excitation mechanisms that can cause the vibrations, an experimental campaign was conducted to measure simultaneously the wind pressure on the surface of a circular cylinder in the atmospheric boundary layer and the acceleration of this cylinder. The pressure and acceleration measurements were used to investigate the interaction between the cylinder and the turbulent wind in subcritical and critical Reynolds number ranges. The study revealed several effects of turbulence in wind in the atmospheric boundary layer on the critical transition, including the promotion of early critical transition, the attenuation of the single separation bubble, and the early cessation of the coherent vortex shedding. A coherent fluctuating axial flow component in the wake of circular cylinders yawed to the flow, which has been previously observed in wind tunnel tests in smooth flow and postulated to be critical for the onset of dry cylinder vibration at high reduced velocity, was not observed in the present experiment.