Design Of Rudder Propeller Of Amphibious Ship And Analysis Of Its Hydrodynamic Performance

Taking the aquatic plants management of rivers,lakes,wetlands and tidal flats as the application background,the research group plans to develop an amphibious grass harvesting ship.At present,the common water propulsion method of aquatic grass harvesting ships is paddle wheel or fixed propeller propulsion.In view of the low efficiency of the paddle wheel drive,the fixed propeller steering needs to rely on the rudder,and the steering in the water is not flexible enough,combined with the characteristics of the amphibious grass harvester,a kind of hydraulically driven rudder propeller was designed in this paper,in order to improve water propulsion efficiency of amphibious grass harvester and make it steering more flexible.The main work completed in this article is as follows:(1)Determination of the design plan of the amphibious ship's underwater propulsion system: This paper summarizes and analyzes the domestic and international research status of the amphibious ship's underwater propulsion system,and determines the design plan of the amphibious ship's underwater propulsion system based on the amphibious ship's working environment and application requirements.(2)Design of propulsion plan of full-rotation rudder propeller: Compare the characteristics of the current propeller and determine the propulsion plan of full-rotation rudder propeller of the amphibious ship.Clarify the design requirements of the amphibious ship's underwater propulsion,and complete the amphibious ship's full-rotation rudder propeller mechanical system design.Determine the transmission mechanism according to the transmission principle,use SolidWorks to complete the three-dimensional structural model of the rudder propeller of the amphibious ship,and make a preliminary calculation of the resistance of the ship to provide a basis for the design of the hydraulic system.(3)Design of hydraulic system and control system of rudder propeller: complete the design and selection of hydraulic unit and electric control unit,determine control plan,write control program,and realize control of rudder propeller.Perform power test on the hydraulic pump in the hydraulic system to verify the reliability of the hydraulic system.(4)Finite element strength analysis of the rudder housing and the transmission gear drive shaft of the full-rotation rudder propeller: when the full-rotation propeller slewing shell is subjected to reverse thrust,the structural strength is sufficient,and the ring will not break,ensuring the rudder stable.The transmission gear and the transmission shaft will not bend and deform the tooth surface when transmitting torque,and the transmission mechanism is stable and reliable.(5)CFD-based hydrodynamic performance analysis of amphibious ship's full-rotation rudder propeller: By simplifying the amphibious ship's hull model and using CFD software STAR-CCM + to perform real-scale simulation analysis,the amphibious ship's sailing resistance under full load is calculated.Through self-propelled analysis and calculation of the amphibious ship,the propeller pitch ratio of the full-rotation propulsion device was 1.0774.The amphibious ship's slewing performance at a rudder angle of 30°was calculated,and the minimum slewing radius of the amphibious ship was 11 meters,which verified that the amphibious ship's rudder propeller had good slewing characteristics.(6)Rudder propeller no-load simulation test: Propeller speed data analysis through the realtime feedback of the speed sensor in the propeller open water test,the propeller speed error is 5.3%;the deviation between the target turning angle of the steering control and the actual turning angle in the rudder test The range is from-2.1°to 1.8°.