Effect of Elastic Deformation of the Journal Bearing Shell on its Dynamic Stability
The stability of the plain cylindrical journal bearing having an elastic shell (liner) is investigated in this work. A perturbed Reynolds equation is used to determine the unsteady components resulting from given small excitations of the bearing journal. The coupled non-linear perturbation dynamic equations for angular and linear motions of the journal carrying a single mass are solved for different values of the steady state eccentricity ratio and the elastic coefficient of the liner. Values of the stability numbers which give critically stable conditions of motion are determined for each case. It was found in this work that increasing the elasticity of the bearing liner resulted in an increase in bearing stability for eccentricity ratios over approximately 0.45. The opposite was observed for eccentricity ratios below this value. It was also found that shorter bearings are less stable than longer bearings for any value of the elastic coefficient.
Keywordselastohydrodynamics elastohydrodynamic lubrication elastic deformation of bearing shell (liner) bearings dynamic stability stability of hydrodynamic bearings
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