| Autor: |
Bokaian, Alireza, Geoola, Farhad |
| Zdroj: |
Journal of Engineering Mechanics; May 1985, Vol. 111 Issue: 5 p591-609, 19p |
| Abstrakt: |
Measurements are presented of the response of a rigid smooth rectangular prism, free to oscillate laterally against linear springs in a uniform flow. The prism was of side ratio 1:2 with the broader side facing the flow direction. The experiments also encompassed wake observations behind the prism when fixed, as well as determination of the lift forces on the fixed prism as a function of angle of flow attack. Dynamic tests showed that an increase in structural damping generally causes the instability to begin at a higher flow speed. The behavior of the cylinder showed differing features depending on the level of the response parameter. For low values of the response parameter, the vortex lock‐in suppressed the galloping instability in the vicinity of the vortex‐resonance speed. In lock‐in re´gime, the vibration frequency showed a considerable variation with flow speed. For high values of the response parameter, the galloping became separated from vortex‐resonance. Whereas turbulence was found to have no appreciable effect on vortex lock‐in, it had profound effects on galloping oscillation. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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