Prediction of Stiffness and Damping Coefficients for Centrifugal Compressor Labyrinth Seals

Abstract

A theory is presented for the calculation of stiffness and damping coefficients of the fluid-rotor interaction in centrifugal compressor labyrinth seals based on turbulent flow calculations. The theory has been confirmed by measurements on labyrinth test stands and on a centrifugal compressor impeller shroud seal at pressures up to 140 bar. Predicted rotor stability limits based on the theory are in agreement with those observed in real compressors.