The flow between a stationary cylinder and a downstream elastic cylinder in cruciform arrangement

The flow past a stationary circular cylinder and a downstream elastic circular cylinder in cruciform arrangement is investigated at a constant Reynolds number of 150. The virtual boundary method is employed in this study. After the validation of the numerical method, two cases are simulated. In Case 1, both cylinders are stationary. A critical spacing is found to be about three diameters (L/D=3)(L/D=3). Beyond this critical spacing, the modification of the wake of the upstream cylinder due to the presence of the downstream cylinder is limited to the mixed region, whereas below this critical spacing, the influenced region is significantly enlarged. In Case 2, we let the downstream cylinder vibrate in response to the fluid forces acting on it, and the vibration is modeled by a spring-damper-mass system. The results show that the peak amplitude of vibrations for the cruciform arrangement is lower than that for an isolated cylinder, and the resonance region is wider than that of an isolated cylinder.