Study On Lubrication And Load Carrying Characteristics Of Rubber-plastic Multilayer Composite Water-lubricated Bearings

Due to the limitations of material properties,single layer water-lubricated bearings usually cannot meet the requirements of lubrication and damping performance simultaneously.To solve the problem,rubber with good damping performance and plastic with good friction performance are superposed to form a rubber-plastic double-layer composite water-lubricated bearing,with rubber as the damping layer and plastic as the friction layer,thereby improving the load carrying capacity and reducing the power consumption and vibration noise.The purpose of this thesis is to study the lubrication and load carrying characteristics of rubber-plastic multilayer layer composite water-lubricated bearing,providing guidance for the design and application of this type of bearings.Based on ANSYS Workbench,fluid-structure interaction(FSI)analyses are conducted to study the influence of bearing structure and operating conditions on bush deformation and bearing load carrying characteristics.Modal analysis and harmonic response analyses are conducted to study the influence of bearing structural parameters on the modal natural frequency and displacement frequency response of the bearing.The main research contents and conclusions are as follows:(1)By comparing and analyzing the calculation results of one-way coupling and twoway FSI,the characteristics and changing rule of bearing deformation distribution with load,rotational speed,bearing thickness,and elastic modulus were studied.The results show that the deformation of the bearing mainly occurs in the rubber layer,and the deformation of the rubber layer bush affects the shape of the plastic layer bush,and causes the overall movement of plastic layer bush.As the load increases,the bush deformation increases,and the stiffness coefficient of the bush decreases.As the thickness of the plastic layer bush increases,the total bush deformation decreases approximately linearly,and the stiffness coefficient of the bearing increases.However,the elastic modulus of the plastic layer bush and rotational speed have a relatively small impact on the total bush deformation and stiffness coefficient of the bearing.(2)Based on the two-way fluid-structure interaction method,the lubrication and load carrying characteristics of rubber-plastic double-layer composite water-lubricated bearings,rubber bearings,and plastic bearings under the same working condition were compared and analyzed.The effects of load,rotational speed,bush elastic modulus,and bush thickness distribution on the lubrication and load carrying characteristics of double-layer bearings were studied.The results show that the lubrication and load carrying characteristics of double-layer bearings are close to those of plastic bearings;With the increase of rotational speed and eccentricity ratio,the maximum pressure of the water film,the maximum bush deformation,and the load carrying capacity of the double-layer bearing increase significantly.The elastic modulus of the bush has a significant influence on the maximum bush deformation,but has little impact on other lubrication parameters.The bush thickness distribution affects the deformation distribution of rubber and plastic layer bushes,but has little effect on the total bush deformation.(3)The influence of bearing pad thickness,elastic modulus,bearing length,and bearing inner diameter on the vibration characteristics of this type of bearing were studied by modal analysis and harmonic response analysis.The results show that as the thickness of the rubber layer bush increases,the bearing modal natural frequency and displacement peak frequency decreases.As the elastic modulus of the plastic layer bush increases,the bearing modal natural frequency and displacement peak frequency increases.The bearing length has a small impact on the bearing modal natural frequency and displacement peak frequency,but the bearing inner diameter has a significant impact on the bearing modal natural frequency and displacement peak frequency.As the bearing inner diameter increases,the bearing modal natural frequency and displacement peak frequency decreases.