Probability and distribution of green water events and pressures

A.D. Boon, P.R. Wellens*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

24 Downloads (Pure)

Abstract

This article proposes a method to quantify, first, the probability of occurrence of green water and, second, the expected maximum pressures during green water events using their statistical distribution for ships at forward speed. A large green water data set which represents 1945 hours of continuous sailing on full scale with different sea states, forward speeds and drafts was obtained with model test experiments in a wave–current tank. The data of the experiment are available as open data through https://doi.org/10.4121/21031981. With the large data set obtained, the distribution of the time between green water occurrences is identified as exponential, indicating that when green water occurs is independent of the time since the last occurrence. Two methods were compared to estimate the probability of green water occurrence. One method is based on the probability of water exceeding the deck and one on a ship’s freeboard and the significant wave height, the former being in better agreement with the data, the latter being more practical for designers. The maximum pressures caused by green water are distributed according to the Fréchet distribution, also called extreme value distribution II. With the newly identified distributions, finally, an equation to calculate the probability of a pressure limit being exceeded for a ship in operation is formulated.
Original languageEnglish
Article number112429
Number of pages14
JournalOcean Engineering
Volume264
DOIs
Publication statusPublished - 2022

Keywords

  • Green water
  • Large data set
  • Long-running experiments
  • Wave–current tank
  • Probability
  • Statistical distribution pressures

Fingerprint

Dive into the research topics of 'Probability and distribution of green water events and pressures'. Together they form a unique fingerprint.

Cite this