Abstract
In this paper, the modelling of strong parametric resonance in head seas is investigated. Non-linear equations of ship motions in waves describing the couplings between heave, roll and pitch are contemplated. A third-order mathematical model is introduced, aimed at describing strong parametric excitation associated with cyclic changes of the ship restoring characteristics. A derivative model is employed to describe the coupled restoring actions up to third order. Non-linear coupling coefficients are analytically derived in terms of hull form characteristics. The main theoretical aspects of the new model are discussed. Numerical simulations obtained from the derived third-order non-linear mathematical model are compared to experimental results, corresponding to excessive motions of the model of a transom stern fishing vessel in head seas. It is shown that this enhanced model gives very realistic results and a much better comparison with the experiments than a second-order model.
Original language | English |
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Pages (from-to) | 1853-1883 |
Number of pages | 31 |
Journal | Ocean Engineering |
Volume | 33 |
Issue number | 14-15 |
Early online date | 27 Mar 2006 |
DOIs | |
Publication status | Published - 31 Oct 2006 |
Keywords
- Hill equation
- non-linear equations
- parametric resonance
- roll motion
- ship motions
- ship stability