Analysis of the Hydroelastic Performance of Very Large Floating Structures Based on Multimodules Beam Theory

Abstract

The hydroelastic behavior of very large floating structures (VLFSs) is investigated based on the proposed multimodules beam theory (MBT). To carry out the analysis, the VLFS is first divided into multiple submodules that are connected through their gravity center by a spatial beam with specific stiffness. The external force exerted on the submodules includes the wave hydrodynamic force as well as the beam bending force due to the relative displacements of different submodules. The wave hydrodynamic force is computed based on three-dimensional potential theory. The beam bending force is expressed in the form of a stiffness matrix. The motion response defined at the gravity center of the submodules is solved by the multibody hydrodynamic control equations; then both the displacement and the structure bending moment of the VLFS are determined from the stiffness matrix equations. To account for the moving point mass effects, the proposed method is extended to the time domain based on impulse response function (IRF) theory. The method is verified by comparison with existing results. Detailed results through the displacement and bending moment of the VLFS are provided to show the influence of the number of the submodules and the influence of the moving point mass.

Predictions of Ship Extreme Hydroelastic Load Responses in Harsh Irregular Waves and Hull Girder Ultimate Strength Assessment

“…To date, majority of the literature work are focusing on the investigation of ship hydroelastic responses in regular waves [20][21][22]. However, the realistic irregular waves are much more complex compared with the regular waves and they are associated with strongly nonlinearity and randomicity.…”

The Effects of Moving Load on the Hydroelastic Response of a Very Large Floating Structure

“…Sun et al [7] extended the method proposed by Lu et al [6] to be applicable for the hydroelastic response of a hinged VLFS in waves (in frequency domain). Other applications of this method can be referred to Xu et al [8] and Zhang et al [9].…”