The GreenWater project started in 2017. GreenWater fits in a series of research projects about ship hydro-structural response, including seakeeping and bow slamming. The project was carried out mainly by ABS, Bureau Veritas, DNV GL, Lloyd’s Register and MARIN.

Ship design loads for extreme wave impacts are hard to define. The main topic of GreenWater was the prediction of impact loads due to green water flowing over the bow, hitting the deck structure of a ship at forward speed. Green water events do not occur at every wave encounter, which makes obtaining reliable statistics challenging. The occurrence of green water also depends on the incoming waves, the ship motions and the deck structure layout. This complexity requires high-fidelity tools such as CFD to obtain the correct loads.

GreenWater focuses both on the prediction of green water events in long duration wave time traces (screening) and on the prediction of the loads in a given event. It was found that indicators such as the relative wave elevation and the undisturbed wave crest height can be used to predict green water events. It was also shown that the detailed loads can then be predicted, if the wave conditions are modelled accurately.