1995 Fiscal Year Final Research Report Summary
Three-dimensional Instability of the Flow Induced around an Oscillating Cylinder in a Density Stratified Fluid at Rest
Project/Area Number |
06640528
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
物理学一般
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Research Institution | KYUSYU UNIVERSITY |
Principal Investigator |
TATSUNO Masakazu Kyushu University, Research Institute for Applied Mechanics, Associate Professor, 応用力学研究所, 助教授 (70038553)
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Co-Investigator(Kenkyū-buntansha) |
KARASUDANI Takashi Kyushu University, Research Institute for Applied Mechanics, Research Associate, 応用力学研究所, 助手 (30150527)
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Project Period (FY) |
1994 – 1995
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Keywords | Stratified Fluid / Oscillating Motion / Non-linearlity / Secondary Flow / Three-dimensional Instability |
Research Abstract |
The structures of the flow induced by a vertical circular cylinder performing transverse oscillations in a linearly stratified fluid at rest are investigated. The density gradient inhibits the onset of the three-dimensional instability. The instability appears as regularly spaced streaked flows along the cylinder axis. Each streaked flow is shed being oscillated along the cylinder surface. Regularly spaced streaked flows arrange themselves alternately along the cylinder axis as the oscillating motion of a streaked flow is 180゚ out of phase with adjacent streaked flows. When the non-dimensional amplitude or frequencies are increased beyond critical values, the streaked flows generated alternately along the cylinder axis do not oscillate along the cylinder surface but extend straight in the direction of cylinder oscillation in the same manner as in the homogeneous fluid.
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Research Products
(2 results)