Critical Speed of Hyperbolic Disks and Eccentricity Effects on The Stability of The Rotor Bearing System


The critical speed of hyperbolic disks for the selected model is calculatedin three different cases, anisotropic material and thermal case, isotropicmaterial and thermal case finally isotropic material and thermal withgenerated heat case. The second case is found to be the best because thecritical speed occurs above maximum speed values.For recognition of the eccentricity (e) effects on the stability, the originalbearings of the selected model were tilting pads bearing replaced byadjustable hydrodynamic pads bearing. The results proved that stabilitycriteria (Sc), critical mass (Mc), whirling frequency ratio ( - 2fn ) of variablerotational speed of the adjustable hydrodynamic pads bearing are stable forthe range of eccentricity (e) about 0.02 mm to 0.09 mm. Finally thethermohydrodynamic (THD) analysis of eccentricity ratio (e) has effects onthe stability of the rotor-bearing system.