Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni- and Bi-Directional Waves

To predict the wave loads of a flexible trimaran in different wave fields, a one-way interaction numerical simulation method is proposed by integrating the fluid solver (Star-CCM+) and structural solver (Abaqus). Differing from the existing coupled CFD-FEA method for monohull ships in head waves, the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be obtained. Firstly, verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step schemes. Discussion on the wave elevation of uni- and bi-directional waves is also carried out. Then a comprehensive analysis on the structural responses of the trimaran in different unidirectional regular wave and bi-directional cross sea conditions is carried out, respectively. Finally, the differences in structural response characteristics of trimaran in different wave fields are studied. The results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations.