Analysis of Nonlinear Lubrication Dynamic Characteristics of Journal Bearings
Linear dynamic characteristic parameters provide a more convenient way for bearing analysis,but there are large errors in the analysis and calculation of the journal bearings with strong nonlinear behavior of oil film vortex and oil film oscillation.The theoretical analysis of the dynamic characteristics of the journal bearing was carried out,and the mathe-matical models of linear and nonlinear stiffness and damping coefficients were established.The numerical solution was car-ried out through the finite difference method,and the influence of different parameters such as disturbing force,Sommerfeld number,and eccentricity rate,on the model of linear stiffness and damping coefficients and the model of nonlinear stiffness and damping coefficients was analyzed.The results show that the linearized lubrication dynamic characteristic parameters cannot describe the strong nonlinear phenomena such as oil film vortex and oil film oscillation of the journal bearing,and it is necessary to introduce the nonlinear dynamic characteristic parameters to describe such phenomena.With the increase of Sommerfeld number,the difference between the nonlinear coefficient oil film force and the linear coefficient oil film force decreases and then increases,and the deviation between the stiffness and damping coefficients considering the horizontal force and the stiffness and damping coefficients without considering the horizontal force is reduced.The absolute values of the nonlinear stiffness and damping coefficients is far more than the values of the linear stiffness and damping coefficients when the eccentricity is less than 0.2 and greater than 0.85.
journal bearingnonlinear dynamic characteristicstiffness coefficientdamping coefficientSommerfeld number
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万方数据
