Analysis Of Bearing Lubrication Characteristics Of Ship Propulsion Shaft Dynamic Calibration

The ship propulsion shaft system is an important part of the ship's power system.During operation,it must withstand complex dynamic loads and stresses.Therefore,the dynamic alignment quality of the shaft system has the great significance in the normal work of the ship propulsion shaft system and the safety of the ship's navigation.There are many factors that affect the quality of the dynamic alignment of the ship's shafting.Among the many dynamic influencing factors,the bearing lubrication characteristic is the most basic factor,which directly affects the shafting operation normally.In this paper,based on the principle of hydrodynamic lubrication,the application of finite difference method and finite element method,combined with MATLAB numerical calculation software and ANSYS finite element software,etc.,has carried out a series of analysis and research on the influence of marine sliding bearing lubrication characteristics on shaft alignment.First,the two-dimensional Reynolds equation is solved by the finite difference method,and the numerical simulation of MATLAB is used to study the oil film thickness and pressure distribution in the marine sliding bearing at different speeds,eccentricity,and oil viscosity,as well as the relationship between speed and eccentricity.Aiming at the actual situation of the deflection of the end of the ship's stern shaft under the concentrated load of the propeller,the film thickness equation of the ship's oil-lubricated stern bearing that takes into account the stern angle of the stern shaft is deduced,and the effect of the shafting angle on the bearing lubrication is analyzed.Secondly,this paper combines the principle of reasonable alignment of the shaft system,considers the thickness of the bearing oil film,and regards the minimum oil film thickness as the equivalent displacement of the bearing.A dynamic alignment model considering the thickness of the bearing oil film is established.The change value of the oil film thickness under the dynamics of the ship's propulsion shafting is taken as the independent variable included in the rational alignment algorithm of the shaft system.The existing algorithm is optimized to obtain the actual bearing load of the ship in the running state.Finally,considering the oil film stiffness,the bearing oil film stiffness was solved using the small disturbance method,and a shafting support model considering the oil film stiffness was established.The effect of the oil film stiffness on the bearing load was verified by calculation on the ship propulsion shafting comprehensive experimental platform.At the sametime,the ANSYS Workbench simulation software was used to simulate and analyze the lateral vibration of the shaft system considering bearing stiffness.