Numerical and Experimental Studies of Interaction between FPSO and Focusing Waves

This paper presents the experimental and numerical investigations on the interaction between a simplified FPSO and focusing waves. The laboratory experiments are carried out in the 3D wave basin at the University of Plymouth. The FPSO is either fixed or moored in the waves. The wave elevations at different locations, pressure time histories and the motions of the FPSO are recorded for different wave conditions. The numerical work is conducted at the City University London using the Quasi Arbitrary Lagrangian Eulerian Finite Element Method (QALE-FEM) based on the fully nonlinear potential theory (FNPT). In order to reproduce the incoming waves measured during the experiments, the time domain self-correction technique existing in literature for generating waves in numerical wave tank is modified, improved and incorporated in the QALE-FEM method in this paper. The self-adaptive wavemaker is also incorporated to reduce the wave reflection. The results show that the modified time domain selfcorrection technique works well and that the wave elevations, the pressure on the FPSO surface and the motion of the FPSO subjected to extreme waves without breaking produced by the QALE-FEM have acceptable agreement with the experimental data.