Experimental rotordynamic force coefficients and leakage for a four-blade, two-four pocket gas damper seal are presented and compared to predictions based on a one control volume bulk-flow model. The test rig comprises a vertical shaft and a test seal housing and flexible structure suspended from a rigid centering frame. The experiments were conducted at increasing rotor speeds to 6000 rpm and inlet/exit pressure ratios from 1.0 to 3.0. The seal force coefficients are obtained from impact response measurements of the seal and flexible structure using a frequency domain parameter identification technique. Both measurements and predictions show the seal direct stiffness and damping coefficients are proportional to the inlet/exit pressure ratio and insensitive to rotor speed. The agreement between experimental results and analytical predictions is acceptable. Predicted cross-coupled stiffness coefficients are of small amplitude. However, the test results evidence cross-coupled stiffnesses without journal rotation due to a structural asymmetry induced by the external pressurization into the seal. [S0742-4787(00)04201-6]
Dynamic Force Coefficients of a Multiple-Blade, Multiple-Pocket Gas Damper Seal: Test Results and Predictions
Contributed by the Tribology Division of THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS and presented at the STLE/ASME Tribology Conference, Orlando, FL, October 10–13, 1999. Manuscript received by the Tribology Division, February 4, 1999; revised manuscript received June 29, 1999. Paper No. 99-Trib-35. Associate Technical Editor: D. P. Fleming.
Li , J., Aguilar , R., Andre´s , L. S., and Vance , J. M. (June 29, 1999). "Dynamic Force Coefficients of a Multiple-Blade, Multiple-Pocket Gas Damper Seal: Test Results and Predictions ." ASME. J. Tribol. January 2000; 122(1): 317–322. https://doi.org/10.1115/1.555360
Download citation file: