Rotor-bearing system characteristics, such as mode shapes and their associated natural frequencies and damping ratios are essential to diagnose and correct vibration problems during system operation. Of the above characteristics, reliable identification of fluid film bearing force parameters, i.e. stiffness and damping coefficients, is one of the most difficult to achieve, in particular during field operation. Results of an enhanced method to estimate support force coefficients in flexible rotor-bearing systems based on imbalance response measurements obtained near the bearing locations are presented herein. The procedure can be conducted on site with minimal instrumentation. A test flexible rotor mounted on two-lobe hydrodynamic bearings is used to validate the identification procedure. Imbalance response measurements for various imbalance magnitudes are obtained near the bearing locations and also at rotor mid-span. At shaft speeds around the bending critical speed, the displacements at rotor mid span are an order of magnitude larger than the shaft displacements at the bearings. The identification procedure renders reliable bearing force coefficients for shaft speeds between 1 krpm and 4 krpm. The sensitivity of the method and derived parameters to noise in the measurements is also quantified.
Identification of Bearing Force Coefficients in Flexible Rotors: Extensions to a Field Method
- Views Icon Views
- Share Icon Share
- Search Site
San Andre´s, L, & De Santiago, O. "Identification of Bearing Force Coefficients in Flexible Rotors: Extensions to a Field Method." Proceedings of the World Tribology Congress III. World Tribology Congress III, Volume 2. Washington, D.C., USA. September 12–16, 2005. pp. 47-48. ASME. https://doi.org/10.1115/WTC2005-63276
Download citation file: