Study On Thermal Elastohydrodynamic Lubrication Characteristics Of Water Lubricated Rubber Bearings

Based on the elastic deformation of rubber layer and the theory of hydrodynamic lubrication,the thermal-fluid-solid coupling model of water lubricated rubber bearings is established in this dissertation,considering the effect of medium temperature on the characteristics of water lubricated rubber bearings,.The effect of different parameters on the thermoplastic lubrication of water lubricated rubber bearings is studied by finite element method and finite volume method.The main contents and conclusions are summarized as follows:(1)The thermal-fluid-solid coupling model of water lubricated rubber bearings is established.The appropriate boundary conditions and the calculation method of the load capacity,friction and friction coefficient of water lubricated rubber bearing are determined through the analysis of the actual operation of the bearings.The mechanical properties tests of the rubber materials are carried out,and the model parameters of the mechanical properties of the rubber materials are obtained through experiments.The parameters of the materials are determined according to the actual situation of the research contents.(2)The effect of water temperature on the lubrication characteristics of the water lubricated rubber bearings with sixteen grooves is analyzed.The effects of water film pressure,flow velocity and rubber layer are studied.The load capacity,friction and friction coefficient of water film are calculated.The results show that when the temperature of the lubrication medium is low,the hydrodynamic effect of fluid is better,the water film pressure and the rubber layer deformation increase.Compared with the high temperature lubrication state,with the temperature decreasing,the viscosity of the water becomes large,the continuity of water film turns to better,and bearing capacity of water film is superior.(3)Based on the two-way thermal-fluid-solid coupling model of water lubricated rubber bearings,the influence of journal rotation speed,eccentricity ratio and salinity of lubricating medium on the thermoplastic lubrication characteristics of water lubricated rubber bearings is discussed.The results show that the pressure of the water film and the deformation of the rubber layer increase,with the journal speed and eccentricity ratio increasing,especially at the eccentricity,the load capacity increases and the coefficient of friction decreases.But the eccentricity ratio being too large or too small are not conducive to the continuity of water film.The speed increasing in a certain range,the water film continuity is better.Compared with the water,the water film pressure,rubber layer deformation and bearing capacity increase,and the friction coefficient decrease under salt water lubrication conditions.