Experimental investigation on the slamming load of the flat bow of a sea-river link container ship

Slamming phenomenon is a transient process, generating a large impact pressure within a very short duration, which could cause fatigue or deformation of the local structure, even severe structural failure or collapse. Due to the limitation and restrictions on the inland waterway, the new designed sea-river linked ship has a more flat and little draught ship type, which would rise more serious slamming problems when the ship sails from the river into the sea. The slamming load conventionally are investigated within the simplified water entry theories and experiments of wedges and plates. Respect to the flat blunt bow, these theories and experimental methods could not predict the slamming pressure well. In the present paper, a three dimensional wooden model of the bow was adopted, and a series of free-fall water entry experiments with different heights and impact angles were carried out. The slamming pressure and its distributions of the bow of a new sea-river linked ship were obtained, as well as the slamming pressure regression formulas based on the experimental results. In the meanwhile, the air cushion was found between the bottom and the water surface in the case of impact angle α<5°, and could postpone and reduce the slamming peak pressure.