Stability Study Of High Speed Semi-planning Trimaran Hull Forms

High-tech ship shipbuilding has become an important area of development shipbuilding industry compete. High-speed trimaran has become an important ship type with its good performance both in high speed, seakeeping, and easy large-scale. Today trimaran has become a very important ship because of advantages above and has also increased our attention. Now we also have done lots of reaches on trimaran. Now most of the trimaran research focuses on the resistance and seakeeping, and many scholars have made important research results. However, the stability of the trimaran research is also a bit weak. The ship's stability is a basic performance for ships and also very important to ensure our safety. A large number of ship capsize accident shows that the lack of stability is the main reason for the accident. The lack of stability of the ship would cause great loss of life and property of people. It is essential to do some further study for the stability of the trimaran hull forms.In this paper, trimaran NURBS surface models have been built with Maxsurf, the intact and damage stability both in calm water and in fallowing waves have been calculated with Hydromax. The main contents include the following aspects:[1] In order to verify the accuracy calculation method for trimaran stability, we have taken the inclining experiment in the towing tank of the Dalian University of Technology then the results were compared with calculation results. We found that the method we taken has reliability in trimaran's stability calculation. So we could calculate stability of trimaran hull form with this method.[2] Calculated the initial stability and large angle stability of the different trimaran side hull's position, analyzed the influence of the side hull's position to the initial and large angle stability of the trimaran in calm water.[3] Calculated the damage stability of the different trimaran side hull's position and damaged tank's position, analyzed the influence of the side hull's position and damaged tank position to the damage stability of the trimaran in calm water.[4] Calculated the intact stability of the different trimaran side hull's position and wave steepness in following waves, analyzed the influence of the side hull's position and wave steepness to the intact stability of the trimaran in following waves.[5] Calculated the damage stability of the different trimaran side hull's position, damaged tank's position and wave steepness damaged tank's position, analyzed the influence of the side hull's position and damaged tank position to the damage stability of the trimaran in following waves. Finally, according to the results obtained some useful conclusions of the trimaran stability and these may be useful for trimaran design.