Numerical Study on the Motion and Added Resistance of a Trimaran in Stern Waves Using a Hybrid Method

This paper presents a one-way coupling method based on the open-source computational fluid dynamics tool OpenFOAM. This hybrid method that couples the fully nonlinear potential theory (FNPT)-based quasi-arbitrary Lagrangian–Eulerian finite element method (QALE-FEM) with the viscous flow method is applied to simulate the forward movement and motion of a trimaran in stern waves. With this hybrid method and the corresponding solver qaleFOAM, the linear and nonlinear incident waves are generated by the external domain of FNPT-based QALE-FEM. The waves propagate to the internal domain by a transition zone. The interaction between the wave and trimaran model in the internal domain is simulated by the viscous flow method. The validation of the wave generation is carried out first. Then, the motion of the trimaran model in stern waves is simulated. Finally, by changing the forward speed and the wave parameters, the amplitude and time history are obtained to analyze the trimaran’s motion characteristics in stern waves.