In this paper the complete set of modified Reynolds’ equations for the active lubrication is presented. The solution of such a set of equations allows the determination of stiffness and damping coefficients of actively lubricated bearings. These coefficients are not just dependent on Sommerfeld number, as it would be the case of conventional hydrodynamic bearings, but they are also dependent on the excitation frequencies and gains of the control loop. Stiffness as well as damping coefficients can be strongly influenced by the choice of the control strategy, servo valve dynamics and geometry of the orifices distributed over the sliding surface. The dynamic coefficients of tilting-pad bearings with and without active lubrication and their influence on an industrial compressor of 391 Kg, which operates with a maximum speed of 10,200 rpm, are analyzed. In the original compressor design, the bearing housings are mounted on squeeze-film dampers in order to ensure reasonable stability margins during full load condition (high maximum continuous speed). Instead of having a combination of tilting-pad bearings and squeeze-film dampers, another design solution is proposed and theoretically investigated in the present paper, i.e., using actively lubricated bearings. By choosing a suitable set of control gains, it is possible not only to increase the stability of the rotor-bearing system, but also enlarge its operational frequency range.
Feasibility of Applying Active Lubrication to Reduce Vibration in Industrial Compressors
Contributed by the International Gas Turbine Institute (IGTI) of THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS for publication in the ASME JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Paper presented at the International Gas Turbine and Aeroengine Congress and Exhibition, Atlanta, GA, June 16–19; 2003, Paper No. 2003-GT-38225. Manuscript received by IGTI, October 2002, final revision, March 2003. Associate Editor: H. R. Simmons.
- Views Icon Views
- Share Icon Share
- Search Site
Santos, I. F., Nicoletti, R., and Scalabrin, A. (November 24, 2004). "Feasibility of Applying Active Lubrication to Reduce Vibration in Industrial Compressors ." ASME. J. Eng. Gas Turbines Power. October 2004; 126(4): 848–854. https://doi.org/10.1115/1.1765123
Download citation file: