Numerical Simulation Of Ship Maneuvering Considering Riverside Effect

With the introduction of the 13 th Five-Year Water Transportation Plan,the development of inland navigation has been accelerated,and the management effect of the channel system of the Yangtze River is remarkable.The high grade channel system is basically formed,the inland waterways is gradually developing to scale and intensive,the quantity of freight transportation is increasing year by year,and the inland ship is specialized and standardized.According to the 2013-2020 year development outline proposed by the Ministry of transport,the scientific development requirements have been put forward for the construction of water transport in Inland waterways,and the modern inland waterway transportation system in China should be further improved so that the inland waterway can meet the new demand of the new era of smooth,efficient,safe and green.We should give full play to the advantages of Yangtze River golden waterway and inland waterway transportation,and provide a solid foundation for China’s economic development and industrial upgrading.But at the same time,there are still a lot of shallow and narrow inland waterways,such as the Jinsha River,Jialing River,Wujiang River in the upper reaches of the Yangtze River,these mountain rivers are shallow,the river width is smaller,the channel is narrower,the riverside effect and the shallow water effect are prominent.When the ship navigate in shallow and narrow waters,due to the limited water depth and width,the ship’s hydrodynamic change is obvious,which leads to the change of the motion state,and the ship’s handling safety is threatened.Because the study of ship maneuvering in shallow and narrow waters has great application value,experts and scholars at home and abroad have done a lot of research.However,the research results mainly focus on the manipulation of shallow water,and the research on the effect of riverside is less.Therefore,based on the ship maneuvering motion mathematical model indeep water and shallow water,combined with the two-dimensional flow mathematical model,the mathematical model of ship maneuvering motion considering riverside effect is established,which can provide reference for the planning and design of the channel with the influence of riverside.The main contents are as follows:Firstly,the basic principle and solution method of two-dimensional flow mathematical model established in this paper are introduced,and the program of water flow calculation is written by Fortran language.The numerical simulation of water flow is carried out from the boundary of Nuozhadu to No.243 Jiebei of the Lancang River.After verifying the flow mathematical model,it can provide flow field data for the numerical simulation of ship maneuvering.Secondly,based on the MMG model,a mathematical model of ship maneuvering motion with three degrees of freedom in deep waters is established,including the ship maneuvering motion equation and the calculation of the hydrodynamic parameters,and the solution is solved by the Runge-Kutta method.On this basis,considering the influence of shallow water,and set up a mathematical model of ship maneuvering motion in shallow waters.The ship maneuvering motion mathematical model of deep and shallow water is used to carry out the navigation test using real ship parameters,including the static water straight line navigation and the static water cycle performance test,the ship rotation test and the Z type test,and the experimental results under the deep and shallow water condition are compared and analyzed,and the reliability of the ship’s mathematical model is verified.Thirdly,the calculation formulas of shore suction and shore thrust moment at home and abroad are analyzed.Based on the ship maneuvering motion mathematical model in deep and shallow water,the ship maneuvering motion mathematical model considering the riverside effect has been established,and the influence of distance from shore,flow velocity,water depth and ship speed to the effect of riverside is studied,and shown by the ship navigation parameters,the ship’s relative deviation and the Froude number.The results of numerical simulation show that the greater the velocity of the water flow in the same direction with the ship,the stronger the riverside effect;when the ship’s distance from the shore is double ship’s width,the riverside effect is stronger;and when the ship’s distance from the shore is quintupling ship’s width,the riverside effect is weaker;the riverside effect is stronger in shallow water than in deep water;the ship speed is bigger,the riverside effect is stronger.Lastly,a numerical simulation of ship maneuvering motion with shallow water and riverside effect is taken in the section of the Suoluo beach section of the Lancang river in Yunnan Province.By analyzing the ship’s track line and navigation parameters under different working conditions,the ship can sail on the beach under the condition that only shallow water is considered.After further considering the riverside effect,the ship needs to adjust the rudder angle to be able to sail normally.