Annular Gas Seals And Rotordynamics Of Compressors And Turbines.

The possible negative or positive impact of annular seal on rotordynamics of compressors and steam turbines is discussed. The nature of destabilizing forces that can be developed by "seethrough" and interlocking labyrinths is discussed. Improving the rotordynamic behavior of labyrinths via swirl brakes and shunt injection is explained using measured test results. Improving rotordynamics through replacement of labyrinths with either smoothrotor/honeycomb-stator seals (honeycomb seals) or pocket damper seals is also discussed. For long seals (L > 2 in or 50 mm) honeycomb seals leak about a third less than a standard labyrinth, have much higher values of effective damping, and potentially high stiffness values for high-pressure compressors. The pocket damper seal is a patented device with damping values that can be a hundred times higher than a standard labyrinth seal. Recent test results are presented for both seal types, and case studies are cited and reviewed where unstable compressors have been "cured" through application of these seals. DOI https://doi.org/10.21423/R1HT06 Description Tutorial pg. 201-220 Subject Turbomachines Collections Turbomachinery and Pump Symposia Citation Childs, Dara W.; Vance, John M. (1997). Annular Gas Seals And Rotordynamics Of Compressors And Turbines.. Texas A&M University. Turbomachinery Laboratories. Available electronically from http://hdl.handle.net/1969.1/163429. DSpace software copyright © 2002-2016 DuraSpace Contact Us | Send Feedback Theme by Annular Gas Seals And Rotordynamics Of Compressors And Turbines   Introduction to Pump Rotordynamics. vibration amplitudes and isolate structural components in gas jet engines, high performance compressors, and occasionally in water pumps. A squeeze film damper consists of an inner non rotating journal and a stationary outer bearing, both of nearly identical diameters. Figure 4 shows an idealized schematic of this type of fluid film bearing. [5] Annular Gas Seals and Rotordynamics of Compressors and Turbines, D. Childs & J. Vance, Proc. Of the 26th Turbomachinery Symposium, TAMU, pp. 201-220, 1997. [6] Gas Damper Seal Test Results, Theoretical Correlation, and Applications in Design of High-Pressure Compressors, P. De Choudhury, F. Kushner & J. Li, Proc. Of the 29th Turbomachinery Symposium, TAMU, 2001.

[1]  Dara W. Childs,et al.  The Acoustic Influence of Cell Depth on the Rotordynamic Characteristics of Smooth-Rotor/Honeycomb-Stator Annular Gas Seals , 1996 .

[2]  John M. Vance,et al.  Test Results of a New Damper Seal for Vibration Reduction in Turbomachinery , 1995 .

[3]  J. M. Vance,et al.  Rotordynamics of Turbomachinery , 1988 .

[4]  Alain Gelin,et al.  EXPERIENCE IN FULL LOAD TESTING NATURAL GAS CENTRIFUGAL COMPRESSORS FOR ROTORDYNAMICS IMPROVEMENTS , 1996 .

[5]  James M. Sorokes,et al.  Recent Experiences In Full Load Full Pressure Shop Testing Of A High Pressure Gas Injection Centrifugal Compressor. , 1994 .

[6]  Jay Armstrong,et al.  Turbine Instability Solution-Honeycomb Seals. , 1996 .

[7]  Dara W. Childs,et al.  A Comparison of Experimental Rotordynamic Coefficients and Leakage Characteristics Between Hole-Pattern Gas Damper Seals and a Honeycomb Seal , 1997 .

[8]  J. S. Alford,et al.  Protecting Turbomachinery From Self-Excited Rotor Whirl , 1965 .

[9]  R. Gordon Kirk,et al.  A Method for Calculating Labyrinth Seal Inlet Swirl Velocity , 1990 .

[10]  Dara W. Childs,et al.  Theory Versus Experiment for the Rotordynamic Coefficients of Annular Gas Seals: Part 2—Constant-Clearance and Convergent-Tapered Geometry , 1986 .

[11]  Dara W. Childs,et al.  Experimental Results for Labyrinth Gas Seals With Honeycomb Stators: Comparisons to Smooth-Stator Seals and Theoretical Predictions , 1989 .

[12]  Robert X. Perez,et al.  The Use Of Honeycomb Seals In Stabilizing Two Centrifugal Compressors. , 1993 .

[13]  J. W. Lund,et al.  Stability and Damped Critical Speeds of a Flexible Rotor in Fluid-Film Bearings , 1974 .

[14]  Dara W. Childs,et al.  An Entrance Region Friction Factor Model Applied to Annular Seal Analysis: Theory Versus Experiment for Smooth and Honeycomb Seals , 1989 .

[15]  Dara W. Childs,et al.  Annular Honeycomb-Stator Turbulent Gas Seal Analysis Using a New Friction-Factor Model Based on Flat Plate Tests , 1994 .

[16]  C. C. Nelson.  Analysis for leakage and rotordynamic coefficients of surface-roughened tapered annular gas seals , 1984 .

[17]  John K. Whalen,et al.  The Use Of Engineering Thermoplastics For Centrifugal Compressor Labyrinths. , 1994 .

[18]  Dara W. Childs,et al.  Annular honeycomb seals: test results for leakage and rotordynamic coefficients. Comparisons to labyrinth and smooth configurations , 1989 .