A model of significant wave height for reliability assessment of a ship

• Published in: Journal of marine systems Vol. 130; pp. 109 - 123
• Main Authors: Podgórski, Krzysztof, Rychlik, Igor
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-02-2014
• Subjects: band approximation; Earth and Related Environmental Sciences; Fatigue damage; Geovetenskap och miljövetenskap; Hundred years wave; Level crossings; Matematik; Mathematics; Narrow; Narrow band approximation; Natural Sciences; Naturvetenskap; Probability Theory and Statistics; Rainflow cycles; Sannolikhetsteori och statistik; Significant wave heights; Level crossings; Narrow band approximation; Rainflow cycles; Hundred years wave; Significant wave heights; Fatigue damage
• ISSN: 0924-7963; 1879-1573
• DOI: 10.1016/j.jmarsys.2013.03.006

Significant wave heights are modeled by means of a spatial–temporal random Gaussian field. Its dependent structure can be localized by introduction of time and space dependent parameters in the spectrum. The model has the advantage of having a relatively small number of parameters. These parameters have natural physical interpretation and are statistically fitted to represent variability of observed significant wave height records. The fitted spatial–temporal significant wave field allows for prediction of fatigue accumulation in ship details and of extreme responses encountered. The method is exemplified by analyzing a container ship data relevant for North Atlantic trade and the results show a high agreement with actual on-board measurements.
•Means to describe variability of encountered sea states by a vessel are given.•A simple model for significant wave heights variability is proposed.•The model features a small number of parameters with simple physical interpretation.•The damage accumulated in a vessel details and its variability are assessed.•The Rice method yields prediction of the extreme seas encountered by a ship.