Analysis Of Marine Sliding Bearing With Elasto-hydrodynamic Lubrication

As the main bearing structure,radial sliding bearings in the ship power plant is in a large number of tail shaft,intermediate shaft,host crankshaft and other key components.The bearing capacity of the marine sliding bearings,the use of efficiency,reliability,and durability will be directly on the propulsion shaft and host performance impact.Therefore,it is very important to carry out the study of elastic hydrodynamic lubrication of marine radial plain bearings.In this paper,the hydrodynamic lubrication(HD),elastic hydrodynamic lubrication(EHD),thermo-elasto-hydrodynamic lubrication(TEHD)were studied by MatLab.And,this paper carries out lubrication analysis on the different bearing structural parameters,including Shaft inclination angles,Young's modulus,etc.In the first chapter,the research background of marine sliding bearing,the analysis of bearing lubrication and the lubrication characteristics of marine sliding bearing are described.Chapter two accords to the theory of hydrodynamic lubrication,based on the two-dimensional Reynolds equation and Reynolds boundary condition,a finite difference model of full-circle bearing is established,and the two-dimensional pressure distribution of the lubricating liquid film is obtained.After the model is validated,the influence of the eccentricity and aspect ratio of the bearing on the pressure distribution is analyzed.Chapter three accords to the theory of elasto-hydrodynamic lubrication,the elastic deformation distribution and pressure distribution are solved by the finite element method and the finite difference method.At the same time,the static characteristics study of steady-state elasto-hydrodynamic lubrication(including offset angle,bearing capacity,friction coefficient,discharge flow)is carried out by the improved shaft equilibrium position correction method.Chapter four carries out the impact analysis in the thickness distribution and pressure distribution to journal inclination,Young's modulus and trench structure.What's more,the influence of elastic deformation and journal inclination on lubrication under specific eccentricity is compared,and the influence of slot position on lubrication performance.The results show that the change in the peak pressure due to the inclination of the shaft diameter can be ignored when material of bearing is soft,like rubber or nylon,and the slot location is best for non-load areas or the front of convergent wedge.Chapter five accords to the theory of thermo-elastic hydrodynamic lubrication,to solve the pressure distribution based on the generalized Reynolds equation of average flow and Reynolds boundary condition.To solve the three-dimensional temperature distribution based on energy equation of lubricant oil and the heat conduction equation of bearing bush.And this paper writes programming of steady-state TEHD,considering the change of viscosity and density.After verifying the correctness of the program,this paper solves the temperature distribution of interface.Finally,this paper analyzes performance parameters in different conditions by changing rotating speed and load.Thispaper reckons that the lower speed of the rotor,such as the ship tail shaft,can not consider the impact of temperature in general conditions.