摘要 :
We report an experimental study of the swiriling flow generated in the gap between two coaxial corotating disks in an enclosed geometry, i.e. when the flow is enclosed in a cylindrical vessel. In this situation the angular momentu...
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We report an experimental study of the swiriling flow generated in the gap between two coaxial corotating disks in an enclosed geometry, i.e. when the flow is enclosed in a cylindrical vessel. In this situation the angular momentum generated by the disk rotation tends to concentrate in a strong axial vortex. In the range of high Reynodls numbers explored, we show that two regimes exist, depending on the disk angular velocities. When they rotate at quite different speeds, we observe very intermittent fluctuations of the axial vorticity associated with quasi-periodic votex bursting, whereas at comparable rotation rates a more stable vorticity structure is observed. We describe these regimes using global measurements; we also show, using local velocimetry, how the structure of the flow affects the small scale turbulence.
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