This paper studies the slamming responses of a wedge structure for the water entry problem. One steel wedge with stiffened panels with a deadrise angle of 45 degrees and a series of free-drop model tests were carried out. An explicit finite element code is applied to simulate this slamming problem. The peak pressure, duration time and stress responses on wedge structure are obtained. Comparisons of the numerical and experimental results are carried out. Good agreement is achieved. The influence of structural stiffness on slamming responses is also discussed.
Slamming occurs on the ship and ocean structure in a harsh working environment. Slamming is a transient process, and the impact pressure is quite short and large, which will cause local structural deformation or hull structure fatigue, and even the hull structure collapse after failure. The problem of slamming has attracted more and more attention. Since slamming is a complex hydrodynamic phenomenon of interaction between ship and wave, which has the characteristics of locality, instantaneity and rapid mobility, it is quite difficult to study the slamming phenomenon. The research methods on slamming include theoretical analysis, numerical calculation and experimental research.
The slamming problem has been studied since Von Karman (1929). Wagner (1932) introduced the potential flow theory to make the wedge equivalent to a plate based on Von Karman's theory, and the impact pressure was obtained by solving the velocity potential and using the Bernoulli equation. After that, several scholars have carried out extensive research based on Wagner's research. It is noted (Borg,1969; Pierson,1951) that the fluid was simplified to inviscid, incompressible and irrotational, and the effects of liquid surface tension, gravity and air cushion was ignored. Greenhow (1987) considered the influence of gravity on the flow field and used the Boundary Element Method (BEM) to solve the problem of the self-similar flow field.