Abstract A parked wind turbine can be subjected to large yaw angles, which causes vortex shedding. Under some particular inflow conditions, the interaction between shed vorticity and blade structure could lead Vortex-Induced Vibrations (VIV). VIV are an instability where response grows until it reaches a limit cycle oscillation. In this paper, we will focus on last part of response. We see that...

By using a Wiener-Hopf approach, an analytical description is derived of the scattered field of a harmonic sound wave coming out of an open ended annular duct (a semi-infinite cylinder inside of which, coaxially, is a doubly infinite hub), submerged in a subsonic, coaxial, uniform mean flow. The possibility of vortex shedding from the pipe exit edge is included. Explicit expressions are given f...

The cavitation characteristics were experimentally investigated about long circular-cylindrical orifices of various throat lengths including the orifice with a trip wire. Especially, the shedding process of separated vortex cavity was examined in detail with the observation using high-speed photography. The cavitation impact was measured with an accelerometer. As a result, it is found that the ...

The aim of present study is to control the unsteady flow structure downstream of a circular cylinder by use of attached permeable plates. Particle image velocimetry (PIV) technique and dye visualization experiments were performed in deep water and the flow characteristics were evaluated by means of time-averaged streamlines, Reynolds Shear Stress and Turbulent Kinetic Energy concentrations. The...

To understand the physics of the complex vortex flow field of the F/A-18 aircraft during maneuvering at high incidences, a series of flow visualizations were conducted in the IAR 0.38 x 0.51m water tunnel. A 1/72-scale model was tested on the new orbital-platform rotary apparatus at angles of attack from 20o to 65o with sideslip angles in the range 10 . It was found that the aerodynamic behavio...

The sea surface imprints of Atmospheric Vortex Street (AVS) off Aleutian Volcanic Islands, Alaska were observed in two RADARSAT-1 Synthetic Aperture Radar (SAR) images separated by about 11 hours. In both images, three pairs of distinctive vortices shedding in the lee side of two volcanic mountains can be clearly seen. The length and width of the vortex street are about 60-70 km and 20 km, resp...

This paper proposes a generalized model for vortex shedding around static cylinder. is first step to bridge the gap between two existing families of Vortex Induced Vibration (VIV) models , namely (1) stochastic spectral and (2) wake-oscillator with coupled fluid structural equations. The family experimentally-based while second typically rely on theoretical phenomenological concepts. These use ...

Periodic vortex streets, often considered as a model for the organized structures observed in the wake of two-dimensional (2D) bluff bodies, are revisited. After the generation of the shear layers the formation of the vortices is mainly an inviscid process. An intrinsic scaling for the formation of vortex streets is found based on the invariants of motion for 2D inviscid flows; namely the kinet...