Research On The Mechanism And Precontrol Method Of Nonlinear Motion Of Ship In Landslide-induced Wave Area

The rock and soil body on the bank slope of the reservoir slides down after it loses stability,generating landslide-induced wave,which poses a huge threat to the safety of navigation ships,hydraulic structures and coastal personnel.In practical engineering,the study on the spatial propagation characteristics of landslide-induced wave,ship navigation safety and ship maneuvering pre-control is not thorough and complete.Therefore,it is of great theoretical and practical significance to study the nonlinear motion mechanism and pre-control method of ships in landslide-induced wave.In this paper,research has based on the coupled method of the turbulent movement of the landslide body into water,the dynamic mesh technique is used to realize the real-time change of boundary element in the simulation process;establish the slamming model of the landslide body into the water;refine the rapping process of high-speed entry into water;research the change of physical quantity of the landslide and the change of water level at each monitoring point in thechannel.At the same time,according to thenumerical simulation results,designing the corresponding physical model test to analyze the formation and propagation process of landslide-induced wave;to reveal the effects of the width,thickness and ratio of width to thickness on the spatial propagation characteristics of the landslide.Combined with the actual freight volume of the Three Gorges reservoir area,research the influence of landslide type,sailing speed,sailing position and motion state on the strong nonlinear motion of ship.Learn the law of steep wave variation and the climbing of landslide-induced wave during its propagation on section of river,curved section of river,straight river area.This paper revolves around the mechanism and precontrol method of nonlinear motion of ship in landslide-induced wave area.It’s mainly obtains the following results and conclusions:(1)Research on the slamming characteristics of slope body entering water at high speed.The model of water entry impact of landslide is established and verified,combining with the characteristics of the Three Gorges reservoir area river,refining the landslide processes to research the changing characteristics of the water level ofthe landslide along with the slope,position and volume of the landslide,and reveal the changing rules of the water entry velocity and free surface of the landslide.(2)Research on the spatial propagation characteristics of land slid e-induded wave.Based on the status quo of the river course in the Three Gorges Reservoir area,the formation process of landslide-induced wave is analyzed by means of physical model test,studying the influence of the width,thickness and the ratio of width to thickness of the landslide on,the height of the first wave and determining the spatial propagation characteristics of the landslide-induced wave along the course in the straight river course,the curved river course and the landslide section.(3)Experimental study on nonlinear motion characteristics of ships under the influence of landslide-induced wave.Based on the spatial propagation of landslide-induced wave,this paper explores the whole process of the interaction between ship and landslide-induced wave,analyzes the motion characteristics of ship’s roll,pitch,yaw and other degrees of freedom according to typical working conditions,and discusses the influence of sailing position,sailing speed,landslide square and sailing state on the roll motion characteristics of ship.(4)Research on steep variation and climbing characteristics of landslide-induced wave.According to the characteristics of channel model,studying the variation of landslide-induced wave with propagation distance in the area of landslide section,straight channel and bend of channel;revealing the climbing rule of landslide-induced wave around ship.(5)Research on pre-control method of navigation safety for ships in landslide-induced wave.Analyzes the motion mechanism of ships in landslide-induced wave,designs the arrangement of mooring cables,studies the roll motion characteristics of ships in various mooring states,and puts forward the pre-control methods of emergency anchoring and steering of ships in landslide-induced wave.(6)Research on ship maneuverability characteristics in landslide-induced wave.Based on the ship maneuvering theory,the ship maneuvering model in landslide-induced wave is established and verified.Studies the ship movement track in landslide-induced wave,and puts forward the safe maneuverability method for ship navigation.