In the present dissertation, the slamming pressure impact on a forward part of a catamaran hull is analyzed using Finite Element Method. The slamming pressure is determined following the guidelines suggested by the American Bureau of Shipping (ABS). Travelling of a ship in rough seas water impact to the ship because of large vertical relative motions between the ship and the water surface. The slamming phenomenon is the impact of the ship bottom on the water surface with a high velocity. The slamming phenomenon is one of the most destructive phenomena for ships. Ship designers are always trying to decrease slamming induced damages.
The slamming pressure has great importance in structure designs. The probability of slamming is found by defining a threshold relative impact velocity of the slamming occurrence. In the structural design of ship hulls, an estimation of slamming loads is important to avoid substantial damage to the catamaran hull.
When the local angle between the water surface and the body surface is not very small at the impact position, slamming pressure can be used in a static structural response analysis to find local slamming-induced stress. The body can be assumed rigid in hydrodynamic calculations. Some approximations can be made in the analysis.
Models of the forward part for the catamaran are designed which are analyzed base on FEM. ANSYS software is used to analyze and simulate effects of the slamming pressure on the construction of a catamaran hull. Slamming pressure is determined according to the ABS guide for the catamaran building. Results obtained the stress distribution and the deformation on the models of the catamaran.
Recently the topology optimization or layout optimization has become a popular topic in the field of optimal design. It is necessary to apply difficult mathematical and mechanical tools for the solution even in case of simple structures. The mathematical programming tools have some limitations on the number of design variables. Hence, it requires an iterative solution technique to be adopted. In this thesis, it can see that the problem of optimization structural topologies when loads are variable and have a nonzero and the fictitious weight of the structure that contains the cost modified weight of the elements is the overall measure of the problem.
The base frames of a ship is a solid structure for installing machinery. It must ensure durability to withstand the load of an engine and reduce the vibration when the engine is operating. In addition, the base frame should be designed to be easy for assembling and saving materials. Base frames of main engines are designed for assembling in the catamaran. After these, the topology optimization of frames is analyzed by using ANSYS software. The static structure and vibration of base frames are also analyzed. Results obtained the reduction in the weight of engine base frames and found clearly natural frequencies and the harmonic response of base frames in order to avoid resonance.
Noise is simply an unwanted sound. It can be prevented people from performing at maximum ability and efficiency [42]. The main producers of mechanically created noise and vibration are engines on ships. A ship has an engine room to make various kinds of power necessary for the operation of a ship. There are many engines installed in the engine room. The operating of these engines causes loud noise. Noise affects the health and comfort of passengers and crews on board ships. In order to reduce the noise caused by machinery, there are many methods in which installing sound insulation on the wall of engine room is an effect is an effective method to increase sound insulation performance. In this dissertation, the Sound Transmission Loss (STL) of insulation material for the engine room is studied and carried out experiments. From the experimental results, the most effective sound insulation material can be selected.