Control of vortex shedding from a cylinder via geometrical surface disturbances

点击翻译按钮获取中文摘要

Vortex formation from cylindrical structures, under certain circumstances, can result in large-amplitude structural vibrations that are detrimental to their fatigue life and integrity. Hence, the problem of vortex-induced vibration (VIV) is central in many engineering applications. Owing to the recent boom of deepwater riser activities at both Canadian and International waters to bring oil from the seabed to the surface, a pressing demand emerges for efficient control methods of vortex induced vibration. Other situations, in which vortex-induced vibration poses a potential threat, include external flow past structures such as bridges, tall buildings, tall industrial chimneys, antennas, and marine cables and internal flow past heat exchanger tubes. Several forms of surface protrusions are known to alleviate the problem of vortex-induced vibration with diverse degrees of effectiveness and are widely used in a number of key industrial areas. Designers, however, develop these devices through ad hoc experiments with insufficient physical understanding of the controlled flow phenomena in relation to the resulting loading and vibration.