Figure 1: Flooded Wing-tank-cross-duct configuration exposed to regular waves. Experiments, COMFLOW and XMF simulations with fluid inertia and without fluid inertia effects accounted for.


New benchmark Over the last year a new and improved flooding model was developed under MARIN’s well-known XMF framework. This flooding model accounts for flow inertia effects when present, and surpasses the (steady) Bernoulli equations. Inertia effects play a role in the flooding of a cross-flooding duct for example, used to provide the necessary equalisation of flood water through the ship in order to decrease the heel angle after damage has occurred. The highlights of the numerical model and the first results were published at the International Conference on the Stability and Safety of Ships and Ocean Vehicles (STAB 2021) and showed improved correlations compared to the Bernoulli-based flow simulations.


To provide a new benchmark dataset for flooding simulations, MARIN and the Hamburg Ship Model Basin HSVA conducted extensive model test programmes with varying levels of flooding complexity in a cruise ship (MARIN) and Ropax vessel (HSVA).


Large-scale captive flooding tests MARIN conducted unique, large-scale captive flooding tests to assess the flooding of several typical compartment configurations, covering in-, down-, up- and cross-flooding. The effect of air scaling was covered by executing the tests over a range of atmospheric pressures with closed or open ship vent pipes in the Depressurised Wave Basin.


Complicated flooding scenarios were tested in the Seakeeping and Manoeuvring Basin with a free-floating cruise ship with


 Example of a large-scale flooding experiment with a complex labyrinth of cabin compartments, door openings and connecting corridors as found in a cruise ship deck section


substantial external damage and a realistic internal compartmentation covering six decks. Tests were executed in irregular waves up to 7 m high. Typical hydrodynamic aspects such as the roll damping of a damaged ship and the effect of drift velocity were investigated. Experimental test techniques were optimised to open the ship breach at a dedicated time during the test by means of a remotely-controlled magnetic sheet.


First results The first results of the benchmark study demonstrated that existing dynamic flooding simulations are able to predict the capsize phenomena rather well. However, the timescale on which water


progresses through the ship, and the accuracy of water levels in specific compartments shows a wider variation between the different simulation tools. Further publications will follow soon, covering even more complex flooding of the large cruise ship and Ropax vessel tested.


Being in its final year, the FLARE project is organising a series of webinars to update you on the progress of the project and is preparing proposals for the revision of the relevant IMO regulations, thereby significantly contributing to ship passenger safety. The consortium website www.flare-project.eu can be consulted for more information.


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