TY - JOUR
T1 - Effect of an internal nonlinear rotational dissipative element on vortex shedding and vortex-induced vibration of a sprung circular cylinder
AU - Tumkur, Ravi Kumar R.
AU - Pearlstein, Arne J.
AU - Masud, Arif
AU - Gendelman, Oleg V.
AU - Blanchard, Antoine B.
AU - Bergman, Lawrence
AU - Vakakis, Alexander F.
N1 - Publisher Copyright:
© 2017 Cambridge University Press.
PY - 2017/10/10
Y1 - 2017/10/10
N2 - We computationally investigate coupling of a nonlinear rotational dissipative element to a sprung circular cylinder allowed to undergo transverse vortex-induced vibration (VIV) in an incompressible flow. The dissipative element is a 'nonlinear energy sink' (NES), consisting of a mass rotating at fixed radius about the cylinder axis and a linear viscous damper that dissipates energy from the motion of the rotating mass. We consider the Reynolds number range 20≤Re≤ 120, with Re based on cylinder diameter and free-stream velocity, and the cylinder restricted to rectilinear motion transverse to the mean flow. Interaction of this NES with the flow is mediated by the cylinder, whose rectilinear motion is mechanically linked to rotational motion of the NES mass through nonlinear inertial coupling. The rotational NES provides significant 'passive' suppression of VIV. Beyond suppression however, the rotational NES gives rise to a range of qualitatively new behaviours not found in transverse VIV of a sprung cylinder without an NES, or one with a 'rectilinear NES', considered previously. Specifically, the NES can either stabilize or destabilize the steady, symmetric, motionless-cylinder solution and can induce conditions under which suppression of VIV (and concomitant reduction in lift and drag) is accompanied by a greatly elongated region of attached vorticity in the wake, as well as conditions in which the cylinder motion and flow are temporally chaotic at relatively low Re.
AB - We computationally investigate coupling of a nonlinear rotational dissipative element to a sprung circular cylinder allowed to undergo transverse vortex-induced vibration (VIV) in an incompressible flow. The dissipative element is a 'nonlinear energy sink' (NES), consisting of a mass rotating at fixed radius about the cylinder axis and a linear viscous damper that dissipates energy from the motion of the rotating mass. We consider the Reynolds number range 20≤Re≤ 120, with Re based on cylinder diameter and free-stream velocity, and the cylinder restricted to rectilinear motion transverse to the mean flow. Interaction of this NES with the flow is mediated by the cylinder, whose rectilinear motion is mechanically linked to rotational motion of the NES mass through nonlinear inertial coupling. The rotational NES provides significant 'passive' suppression of VIV. Beyond suppression however, the rotational NES gives rise to a range of qualitatively new behaviours not found in transverse VIV of a sprung cylinder without an NES, or one with a 'rectilinear NES', considered previously. Specifically, the NES can either stabilize or destabilize the steady, symmetric, motionless-cylinder solution and can induce conditions under which suppression of VIV (and concomitant reduction in lift and drag) is accompanied by a greatly elongated region of attached vorticity in the wake, as well as conditions in which the cylinder motion and flow are temporally chaotic at relatively low Re.
KW - Chaos
KW - flow-structure interactions
KW - vortex shedding
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U2 - 10.1017/jfm.2017.504
DO - 10.1017/jfm.2017.504
M3 - Article
AN - SCOPUS:85020540116
SN - 0022-1120
VL - 828
SP - 196
EP - 235
JO - Journal of Fluid Mechanics
JF - Journal of Fluid Mechanics
ER -