TY - JOUR
T1 - Phase jump and energy transfer of forced oscillating circular cylinder in uniform flow
AU - Tang, Guoqiang
AU - Lu, Lin
AU - Zhao, Ming
AU - Liu, Mingming
AU - Zong, Zhi
PY - 2017
Y1 - 2017
N2 - The phase jump, energy transfer, and the associated vortex shedding modes of a circular cylinder undergoing forced oscillation normal to the incoming uniform flow are investigated numerically at Reynolds number (Re) of 200. The dependence of the fluid forces on the non-dimensional oscillating amplitude A* = A/D ∈ [0.1, 0.6] and frequency f* = fe/fs ∈ [0.5, 2.0] is examined, where A is the oscillating amplitude, D is the cylinder diameter, fe is the cylinder oscillating frequency, and fs is the Strouhal frequency of fixed cylinder at the same Reynolds number, respectively. The lock-in region is identified by the combination of Fourier analysis and Lissajous phase diagram. The phase difference between displacement and lift fluctuation and the energy transfer between fluid and structure are discussed. Within the lock-in region, a jump in the phase difference is found to occur in the cases with A* = 0.5 and 0.55 without a wake mode transition. The numerical results reveal that the appearance of the phase jump is consistent with the reversal of the energy transfer direction. For the special cases of A* = 0.5 and 0.55, changes in the sign of energy transfer are observed, while no reversal of energy transfer is observed at other amplitudes. The energy transfer direction is either from fluid to cylinder when A* ∈ [0.1, 0.4] or from cylinder to fluid when A* ≥ 0.6. It is confirmed that the energy transfer between fluid and cylinder is not only dependent on cylinder oscillating frequency but also on cylinder oscillating amplitude.
AB - The phase jump, energy transfer, and the associated vortex shedding modes of a circular cylinder undergoing forced oscillation normal to the incoming uniform flow are investigated numerically at Reynolds number (Re) of 200. The dependence of the fluid forces on the non-dimensional oscillating amplitude A* = A/D ∈ [0.1, 0.6] and frequency f* = fe/fs ∈ [0.5, 2.0] is examined, where A is the oscillating amplitude, D is the cylinder diameter, fe is the cylinder oscillating frequency, and fs is the Strouhal frequency of fixed cylinder at the same Reynolds number, respectively. The lock-in region is identified by the combination of Fourier analysis and Lissajous phase diagram. The phase difference between displacement and lift fluctuation and the energy transfer between fluid and structure are discussed. Within the lock-in region, a jump in the phase difference is found to occur in the cases with A* = 0.5 and 0.55 without a wake mode transition. The numerical results reveal that the appearance of the phase jump is consistent with the reversal of the energy transfer direction. For the special cases of A* = 0.5 and 0.55, changes in the sign of energy transfer are observed, while no reversal of energy transfer is observed at other amplitudes. The energy transfer direction is either from fluid to cylinder when A* ∈ [0.1, 0.4] or from cylinder to fluid when A* ≥ 0.6. It is confirmed that the energy transfer between fluid and cylinder is not only dependent on cylinder oscillating frequency but also on cylinder oscillating amplitude.
KW - Navier–Stokes equations
KW - energy transfer
KW - oscillations
UR - http://handle.uws.edu.au:8081/1959.7/uws:36408
U2 - 10.1177/1475090216656950
DO - 10.1177/1475090216656950
M3 - Article
SN - 1475-0902
VL - 231
SP - 496
EP - 510
JO - Proceedings of the Institution of Mechanical Engineers. Part M: Journal of Engineering for the Maritime Environment
JF - Proceedings of the Institution of Mechanical Engineers. Part M: Journal of Engineering for the Maritime Environment
IS - 2
ER -