Wave Interactions Generated by Multi-Ship Unite Moving in Shallow Water
Chen Bo,Wu Jiankang
(Mechanics Department, Huazhong University of Science and Technology, Wuhan, China 430074)

Abstract: Based on Green-Naghdi(G-N) equation, a Wave Equation Model (WEM) and Galerkin finite element method (FEM) with moving grids are combined to investig ate the wave interactions generated by multi-ship moving in shallow water, wher e moving ships are regarded as moving pressure disturbances on free surface. The moving pressure is incorporated into the G-N equation to formulate the interac tions of moving ships and free surface. G-N equation involves nonlinearity and frequency dispersion to account for the effects of finite water depth on ship waves. The numerical examples of Series 60 (C_B=0.6) ships moving in shallow water are presented. Three-dimensional ship wave profiles, wave resist ances and transverse forces are given in three cases of two-ships parallelly moving, a ship moving followed by the other, and three-ships moving with a triangle feature. The numerical results indicate that the ships exp erience an attractive transverse force when two ships move in parallel, and the wave resistance slightly increases; the wave resistance of both ships decrease when a ship moves followed by the other; when three ships move as a triangle the resistance exerted on the leading ship decreases, but increases for the two foll owing ships with weakened attractive transverse force.
Keywords: the Green-Naghdi equation, shallow water, ship waves, wave equation model.