Abstract:
This study aims to explore the phenomenon of Vortex-Induced Vibration (VIV) generated
by cylinder undergoing rotation at different rotation rates (α = 0, 0.25, 0.5, 0.75, and 1) while
being subjected to oscillatory flow in two dimensional numerical simulations. The simulations
use two different Keulegan-Carpenter (KC) numbers KC = 5 and 10, at Reynolds number Re
= 150. A widespread reduced velocities range. This research purpose is to explore the
phenomenon of Vortex-Induced Vibration (VIV) generated by a cylinder undergoing rotation
at different rotation rates ( α = 0, 0.25, 0.5, 0.75, and 1) while being subjected to oscillatory
flow.
The results demonstrate that vibration amplitude in inline and cross-flow directions is
significantly influenced by the rotation provided to cylinder, as well as the KC number and Vr.
However, it is observed that the cross-flow direction vibrations are more profoundly affected
by the rotation. Case of the stationary cylinder (α = 0), the VIV amplitude in cross-flow
direction almost diminishes once the critical value of reduced velocity is surpassed, specifically
Vr = 6 for KC = 5 and Vr = 11 for KC = 10. On other hand, for rotating cylinders (α ≠ 0), the
vibration amplitude reaches zero only at the critical value of reduced velocity. Beyond this
point, it gradually increases and eventually stabilizes.
The critical reduced velocity, which determines the point at which the vibration amplitude
essentially becomes zero, depends on the cylinder's relative motion and is considered the
critical reduced velocity when the effective KC number (KCeff) is very small and same trent
also observed for effective reduced velocity (Vr eff) are small. It should be noted that at
significantly higher reduced velocities, a non-vortex shedding regime occurs, indicating a
distinct flow behavior
