Abbas Dashtimanesh

In recent decades, high-speed craft have become extremely important and various hull shapes have been proposed, designed and built to achieve high speeds. High-speed craft are divided into four groups: monohull, hydro-foil, surface-effect and multi-hull crafts. Here, the main focus is on catamarans, which are part of the group of multi-hull crafts. Studies show that research on catamarans is very limited and there is no comprehensive model to evaluate their performance in calm water. Therefore, in this thesis, the aim is to consider a mathematical model for catamarans that can consider the running attitudes in calm water. In this research, a mathematical model for modeling the dynamics of catamarans is presented using new analytical equations for the zero heel angle mode in calm water. The development of this mathematical model can be an important step in the modeling of catamarans. The modeling method for predicting the running attitudes of catamaran bodies is based on 2D+T theory. In the present thesis, the hydrodynamic pressure has been investigated analytically and numerically, and the results of the wedge entering the water have been investigated numerically, and finally the forces on the vessel and the resistance have been calculated. Finally, comparing the three vessels with the distances of the two demihull and the different deadrise angle, it was concluded that they have better performance at the lesser distances between the two demihull and the lesser deadrise angle