Abstract A systematic experimental investigation to understand the effect of flow and structural non-uniformity on vortex-excited vibrations is underway at the University of Notre Dame's Hessert Center for Aerospace Research. The experiments are designed to investigate the effects of axial taper of a circular cylinder and its interaction with shear in the approach flow on the structural response to vortex shedding. The dynamic response characteristics of a pivoted, tapered circular cylinder subjected to vortex-excited vibrations in a wind tunnel are reported here. In all, six scenarios of tapered pivoted cylinders in uniform and shear flows were investigated. The salient features of the experimental investigations and the experimental observations are presented here as time histories of the structural displacements, structural response amplitudes as a function of flow speed and power spectral densities of the near wake velocity fluctuations. The results of the experimental investigations indicate that the response of axially varying structures to vortex-excited vibrations is quite different from those of uniform cylinders (Balasubramanian et al., J. Fluids. Struct. 14 (2000) 65). The range of locked-in structural response is found to be very sensitive to the relative orientation between the flow-gradient and axial taper of the cylinder.
[1]
T. Sarpkaya.
Fluid Forces on Oscillating Cylinders
,
1978
.
[2]
Tae-Young Chung.
Vortex-induced vibration of flexible cylinders in sheared flows
,
1987
.
[3]
A. Papangelou.
Vortex Shedding from Slender Cones at Low Reynolds Numbers
,
1992
.
[4]
R. Skop,et al.
A new twist on an old model for vortex-excited vibrations
,
1997
.
[5]
A. A. Szewczyk,et al.
On the existence of a critical shear parameter for cellular vortex shedding from cylinders in nonuniform flow
,
1998
.
[6]
Li Li,et al.
THE OCCURRENCE OF LOCK-IN UNDER HIGHLY SHEARED CONDITIONS
,
1996
.
[7]
J. W. Elder,et al.
Steady flow through non-uniform gauzes of arbitrary shape
,
1959,
Journal of Fluid Mechanics.
[8]
C. Williamson,et al.
DYNAMICS OF A HYDROELASTIC CYLINDER WITH VERY LOW MASS AND DAMPING
,
1996
.
[9]
T. Sarpkaya.
Brief Reviews of Some Time-Dependent Flows
,
1992
.
[10]
Fred L. Haan,et al.
VORTEX-EXCITED VIBRATIONS OF UNIFORM PIVOTED CYLINDERS IN UNIFORM AND SHEAR FLOW
,
2000
.