Vortex induced vibration of cylinders with an attached elastic plate

We investigated the effect of attachment of an elastic plate of high aspect ratio (AR= [10, 20]) to leeward side of cylinder undergoing vortex induced vibration at low Reynolds number of 150 using a flow solver based on the curvilinear immersed boundary method coupled with a finite element solver by the partitioned approach. Lock-in was observed when the non-dimensional natural frequency of the elastic plate, the non-dimensional frequency or the inverse of reduced velocity of the cylinder undergoing vibration, and the non-dimensional vortex shedding frequency from the cylinder were close to each other. The elastic plate at resonance was observed to be attaining very high modes of deformation leading to vortex-to-vortex interaction with cylinder. The transverse displacement of the cylinder with an attached elastic plate of length twice the diameter of the cylinder was found to be nearly twice of an isolated cylinder. Further, the lock-in regime in the presence of attached elastic plate was observed to be narrowed when compared to that of an isolated cylinder.