Modeling and Identification of a Nonlinear SDOF Moored Structure, Part 2—Comparisons and Sensitivity Study
- 1 May 2004
- journal article
- Published by ASME International in Journal of Offshore Mechanics and Arctic Engineering
- Vol. 126 (2), 183-190
- https://doi.org/10.1115/1.1710874
Abstract
A system-identification technique based on the Reverse Multiple-Input/Single-Output (R-MI/SO) procedure is applied to identify the parameters of an experimental mooring system exhibiting nonlinear behavior. In Part 1, two nonlinear small-body hydrodynamic Morison type formulations: (A) with a relative-velocity (RV) model, and (B) with an independent-flow-field (IFF) model, are formulated. Their associated nonlinear system-identification algorithms based on the R-MI/SO system-identification technique: (A.1) nonlinear-structure linearly damped, and (A.2) nonlinear-structure coupled hydrodynamically damped for the RV model, and (B.1) nonlinear-structure nonlinearly damped for the IFF model, are developed for an experimental submerged-sphere nonlinear mooring system under ocean waves. The analytic models and the associated algorithms for parametric identification are described. In this companion paper (Part 2), we use the experimentally measured input wave and output system response data and apply the algorithms derived based on the multiple-input/single-output linear analysis of the reverse dynamic systems to identify the system parameters. The two nonlinear models are examined in detail and the most suitable physical representative model is selected for the mooring system considered. A sensitive analysis is conducted to investigate the coupled hydrodynamic forces modeled by the Morison equation, the nonlinear stiffness from mooring lines and the nonlinear response. The appropriateness of each model is discussed in detail.Keywords
This publication has 6 references indexed in Scilit:
- Modeling and Identification of a Nonlinear SDOF Moored Structure, Part 1—Hydrodynamic Models and AlgorithmsJournal of Offshore Mechanics and Arctic Engineering, 2004
- Hydrodynamic Forces on Flexible Offshore StructuresJournal of Engineering Mechanics, 1984
- Further Tests on Ocean Wave Forces on SphereJournal of the Waterway, Port, Coastal and Ocean Division, 1978
- Ocean Wave Forces on a Subsurface SphereJournal of the Waterways and Harbors Division, 1969
- Dynamic Response of a Restrained Sphere in a FluidJournal of the Engineering Mechanics Division, 1967
- The flow field induced by an oscillating sphereJournal of Sound and Vibration, 1965