Study On The Dynamic Characteristics Of Rotor System Supported On The Water Lubricated-Rubber Bearings

The dynamic characteristics of rotor system with water-lubricated rubber bearing is mainly studied in this thesis. Based on the elastohydrodynamic lubrication theory of water-lubricated rubber bearing, its dynamic characteristics are analyzed according to the finite difference method. The dynamic model of rotor system with water-lubricated rubber bearing are discussed based on Lumped parameter method. The natural characteristics, stability and unbalance response of the system are analyzed in last. The main contents and conclusions are summarized as follows:1. The static characteristics of water lubricated rubber bearings are calculated by difference method, focusing on the influence of the elasticity of rubber on its lubrication characteristics of bearing. The results show that the water film rupture boundary location and water film force peak appeared in advance with the increase of eccentricity. The dimensional water film force and film thickness are increased. After considering of the elasticity of rubber, the change of water film pressure and film thickness are significant, and the groove appeared at the peak value position. At the same time, the delay of peak value position is more significant, as well as the tilt of the area of peak. The bearing water film pressure and film thickness are decreased with the increase of elasticity, but the lining deformation is increased.2. The dynamic characteristics of water lubricated rubber bearings are studied by difference method. The results show that several parameters, such as the eccentricity, length-diameter ratio, clearance of the bearing and the rotating speed of rotor, have a great impact on the dynamic performance of water lubricated rubber bearings. The stiffness coefficient and damping coefficient of bearings are increased with the increase of eccentricity. The elasticity of water lubricated rubber bearings causes its damping and stiffness coefficients of the bearings to decrease. The structure of groove of water lubricated rubber bearings also has a great effect on its dynamic characteristics. Bearing groove structure by destroying the continuity of water film, in turn, affect the bearing dynamic characteristics, and lead to the decrease of bearing carrying capacity.3. The dynamic model of rotor system coupled with water lubricated rubber bearings is established, and its dynamic characteristics and the influence of parameters were analyzed. The natural characteristics, stability and unbalance response of the system were mainly studied. The results show that the elasticity has small influence on its critical speed, but which has great influence on the stability of the system. The rubber liner thickness and buoyancy of water lubricated rubber bearings have little influence on the unbalance response of rotor system supported by water lubricated rubber bearings.