The Forms Of Ship Mooring And The Analysis Of Their Hydrodynamic Performance At The Dock

With the development of the international shipping industry, people’s demand for the dock is increasing. With the increase of the dock of the open type and the semi-open type, the natural environment that ship suffers at the dock is getting worse and worse. Therefore, the study of the ship mooring at the dock is a growing concern of researchers. In order to ensure the safety of the mooring ship and loading and unloading of the cargo, it is necessary to analysis hydrodynamic performance for the ship mooring at the dock.At present, most of the study of ship mooring at the dock is by the way of model test, the study by the way of numerical simulation is little.In this paper, based on the three-dimensional potential theory, hydrodynamic performance and forms of mooring is researched by ANSYS-AQWA software. The main contents can be summarized as follows:(1)The hydrodynamics of the ship mooring at the dock is analyzed in the frequency domain. At first, the finite element model is built by ANSYS software. After this, the hydrodynamic performance is analyzed in the frequency domain by AQWA-LINE, which can obtain the changing trend of added mass, radiation damping, RAO, first-order wave excitation force and steady drift force with frequency. It is compared that hydrodynamic performance is influenced by different water depths, different angle of incidence and the presence of the dock.(2)The coupling of the ship mooring at the dock is analyzed in the time domain. Under the combined effects of wind, wave and current, the changed condition of ship’s motion response and mooring lines’ tension is researched in the six degrees of freedom using AQWA-DRIFT module. What’s more, the results of motion response are analyzed by frequency spectrum through fourier transform. On this basis, it is discussed that each component of the frequency response is contributed to motion response.At the same time, it is researched that the coupling results is influenced by the direction of wind,the direction of wave and the direction of current.(3) The optimization of mooring forms and dynamic response analysis are carried out. Using AQWA-DRIFT module, at first, mooring type is optimized along the depth direction, then the fore line, the stern line and the lateral lines are optimized. On this basis, the results of before and after optimization are analyzed. From the ship’s motion response and mooring lines’ tension, it is compared that which is the better between the optimized solutions and original solution. At last, relevant conclusions are drawn.