VIV control and drag reduction with no moving parts
Tóm tắt
This paper presents a new passive VIV (Vortex Induced Vibrations) suppression device that also leads to drag reduction. The device uses the guided porosity concept and is applied in experimental tests conducted for low mass ratio cylindrical models. It is shown that the transversal VIV amplitude is reduced. It is also shown that there is a simultaneous reduction of the drag forces in contrast with strakes, which increase drag. On the other hand, in contrast with the fairings solution, the present device uses no moving parts. To show where to guide the porosity, a brief review with potential flow theory is presented. A brief feasibility investigation is presented by variations on the angle of uniform flow incidence. Finally, an optimized distribution of porosity apparatus is proposed based on the experimental results.
Tài liệu tham khảo
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