A Study Of Ship-Generated Waves And Its Effects On Structures

A panel method based on potential flow theory has been developed to solve the ship waves-body interactions in the time domain. The thesis includes the evaluations of time -domain Green function, ship waves caused by a ship with uniform speed, ship waves interactions with various structures (fixed structures, floating bodies and moored floating bodies).A Kelvin source panel method is applied to solve the wave-making problems. This model can be evaluated by flow around fixed structures. The results for truncated cylinder incurrent are presented as well as the thin ships. The wave-making model developed in this thesis can be applied to the linear wave-making problems of arbitrary bodies including submerged bodies.Due to the huge CPU and mass storage requirements of the time-domain computation, a fast algorithm for time-domain Green function and its derivatives is presented and applied to the ship waves-body interactions. The model is first examined by the diffraction of simple shape bodies (submerged sphere, hemisphere, submerged box and truncated box). The computed wave forces are compared with the frequency-domain results, and they agree very well. The diffraction problems of fixed structures under thin ship waves are considered. The focal points of the work are analyzing the relationships of distance between ship and structures, ship length, ship beam and ship draft with wave forces induced by ship waves.Then, diffraction-radiation problems are examined in context of simple shape bodies (floating box and Wigley hull) and compared with the frequency-domain results or experimental results. The parameter analysis of ship speed, distance between ship and structures, ship length, ship beam and ship draft with wave forces and motion responses of floating bodies by thin ship waves is implemented.In the final application, Wave loads and motion responses are computed with a Wigley hull passing by a moored truncated cylinder. The diffraction-radiation problems are examined by comparing the time domain results with the frequency domain ones and they agree very well. The parameter analysis of ship speed, distance between ship and structures, ship length, ship beam and ship draft with wave forces and motion responses of moored structure by thin ship waves is also implemented.