Complex responses observed in an experimental, nonlinear, moored structural system subjected to nearly periodic wave excitations are examined and compared to the simulations of a newly proposed independent-flow-field (IFF) model in this paper. Variations in wave heights are approximated by additive random perturbations to the dominant periodic component. Simulations show good agreement with the experimental results in both time and frequency domains. Noise effects on the experimental results, including bridging and transition phenomena, are investigated and interpreted by comparing to the simulations of its deterministic counterpart. Possible causes of a chaoticlike experimental result as previously observed are also inferred.
Issue Section:
Technical Papers
Keywords:
experimental,
nonlinear,
random perturbations,
complex,
structural engineering,
offshore installations,
ocean waves,
frequency-domain analysis,
time-domain analysis,
perturbation techniques,
perturbation theory
Topics:
Excitation,
Flow (Dynamics),
Noise (Sound),
Resonance,
Waves,
Wave amplitude,
Attractors,
Mooring
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.Copyright © 2006
by American Society of Mechanical Engineers
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