Numerical prediction of seakeeping and slamming behaviors of a trimaran in short-crest cross waves compared with long-crest regular waves

The ship seakeeping and slamming behaviors in multi-directional waves differ significantly from those in uni-directional waves. Given that a ship operates in short-crest or bi-directional waves during its navigation, it is significant to have a better understanding of the effect of 3-D waves on ship motion and slamming behaviors. In this work, a trimaran is adopted for seakeeping and slamming analysis. Firstly, the bi-directional cross waves, which is selected as the 3-D short-crest waves, are generated by the numerical wave tank. Secondly, the trimaran motion and slamming responses in cross wave fields with different parameters such as relative position, wave length and forward speed are predicted and analyzed. The impact and green water characteristics of the trimaran are observed and analyzed. Finally, the motion responses and pressure distribution of trimaran in short-crest cross waves are compared with those in long-crest regular waves. The conclusions drawn in this work will provide certain guidance for the safety navigation of trimarans under the action of cross waves.