A study of the effects of eccentricity on honeycomb annular gas seals

Abstract

Results are presented which show the effects of eccentricity on high pressure honeycomb and smooth annular gas seals. The results of the experiments indicate the ability to utilize centered seal solutions for rotordynamic coefficients and seal leakage for eccentricities out to 0.5. Results are given that confirm previous results for a low pressure smooth seal testing indicating that the rotordynamic coefficients are affected by eccentricity ratios above approximately 0.2. Experimental results for the high pressure honeycomb and smooth seals are compared with predictions from a numerical program to determine which coefficients are accurately predicted. Leakage predictions are shown to be consistent with the experimental results obtained for honeycomb seals. The results show that cross-coupled stiffness was accurately predicted for both seal types. The accuracy of the other predictions depends on the seal type and the specific condition of interest.