Research On Ship Mooring Performance Under The Combined Action Of Wind And Waves

This thesis is mainly about the research on the ship mooring performance.Mooring system is very important for ship rest,wind and typhoon prevention.The accident of dropping the anchor and go anchoring still occurred from time to time due to lack of research of ship movements under the wind,waves,currents and other environmental effects.At present,anchoring of ships is still mainly based on personal experience.There is an urgent need to study a complete set of methods for assessing the mooring performance of ships.This thesis introduces the design of the mooring system according to the rules of national military standard and CCS,and the wind load,wave and flow load suffered by the ship are analyzed.According to the analysis result,it takes a ship for example to calculate the responding of the ship under the combined action of wind and waves by engineering algorithms and ANSYSAQWA hydrodynamic software respectively,the performance of the mooring is also evaluated.The researches on the ship mooring performance in the thesis are as follow:1.According to the rules of national military standard and CCS,it researches on the methods of the ship mooring system design,and check the safety by an example.2.Based on the ocean wind,waves and flow conditions of the ship,it researches on the loads of the wind,waves and flow calculation methods.3.It uses catenary theory to analyze the force of ship's mooring chain.Based on the environmental loads of ship,the limit mooring force of the ship is analyzed,and the method to evaluate the mooring ability of the ship is obtained.It introduced the engineering calculation and software simulation methods of calculating ship mooring performance in details.4.It takes a ship as an example to research on the limit loads which the ship mooring system could afford under the combined action of wind and waves by engineering calculation and ANSYS-AQWA hydrodynamic software respectively.Mooring line force situation and lie-down chain length is calculated.The response of the ship mooring system is concluded,and the safety and performance of the ship mooring under various conditions is evaluated.Finally,the thesis gives a process to calculate the mooring performance.