Nonlinear rolling response in a regular sea

Article type: Research Article

Authors: Cardo, A.^a | Francescutto, A.^b | Nabergoj, R.^c

Affiliations: [a] Istituto di Architettura Navale, Trieste | [b] Istituto di Fisica, Trieste | [c] Istituto di Fisica, Udine, Italy

Abstract: The rolling motion of a ship has been described by a nonlinear differential equation explicitly taking into account the nonlinearities in both the righting moment and the damping. A perturbative analysis in the main resonance frequency region, relative to a regular beam sea, allows an estimate of the maximum amplitude predictable as a function of the excitation intensity. This is obtained through an algebraic equation from which the approximate solution can be given in an explicit form. To this effect, a simple formula relating the excitation to the maximum rolling is found. A comparison of the theoretical predictions with the experimental results shows quite a good agreement.

DOI: 10.3233/ISP-1984-3136002

Journal: International Shipbuilding Progress, vol. 31, no. 360, pp. 204-206, 1984