A review of recent studies on the control of vortex-induced vibration of circular cylinders

Recent studies of passive and active flow control devices for suppressing vortex-induced vibration (VIV) of circular cylinders are reviewed extensively. The passive control devices include splitter plates, control rods, helical strakes, porous layers and rough surfaces, and the active flow control devices include jet flow, rotating cylinder, and rotating control rods. A splitter plate with a certain length can suppress VIV but very long splitter can cause galloping. One or two control rods located downstream the flow separation points can suppress VIV. VIV suppression using three to eight control rods were also studied and increasing rod number can improve suppression effectiveness. Porous layers with sufficient porosity and thickness can achieve nearly full VIV suppression and generally have better suppression effect than rough surfaces. Helical strakes can suppress VIV well when its pitch ratio is greater than 10 and height is greater than 0.2 times cylinder diameter. If sufficient external energy is used, jet control and rotating control rods can achieve nearly full VIV suppression. Rotating control rods in one direction can suppress VIV but, in another direction, can enhance VIV. Some important conclusions are highlighted in section 4 of this paper.