|Title||Resonance of a flexible plate immersed in a von Karman vortex street|
|Publication Type||Journal Article|
|Year of Publication||2020|
|Authors||Hernandez E.S, Smith SGL, Cros A.|
|Type of Article||Article|
|Keywords||circular-cylinder; Engineering; Euler-Bernoulli beam; Flow-structure interaction; Resonance; street; vortex; wake|
This work presents a theoretical and experimental study of a flexible plate immersed in a von Karman vortex street. The wake is generated in a water flow using a cylindrical obstacle with a Reynolds number lower than 200. The vortices provoke oscillations of a flexible plate whose leading edge is clamped a few cylinder diameters downstream of the obstacle. The oscillation amplitude of the free edge is examined experimentally as the plate length is varied with respect to the wavelength. The value of the peak of the amplitude and the phase shift between the forcing vortices and the plate deflection are consistent with theoretical predictions. These predictions use an Euler-Bernoulli model for the motion of the plate produced by the pressure difference over the plate due to the combined effect of the vortex street and the deflection of the plate. The ratio between the plate length and the wake wavelength for which resonance occurs is fixed by the condition that the natural frequency of the plate is equal to the vortex frequency.