Identification of Stiffness, Damping and Inertia Coefficients of Annular Turbulent Seals
An important assumption for the reliability of high speed centrifugal pumps is a good rotordynamic behavior. Connected to this problem hydraulic forces acting on the rotor are of major importance. It is well known that neck ring seals as well as interstage seals (Fig. 1) may have a large influence on the bending vibrations of a pump rotor. Besides their designed function of reducing the leakage flow between the impeller outlet and inlet or between two adjacent pump stages, the contactless seals have the potential to develop significant forces. This type of forces, created by lateral rotor vibrations can be described by a linear model with stiffness, damping and inertia coefficients.
KeywordsFrequency Response Function Leakage Flow Inertia Coefficient Impeller Outlet Pump Rotor
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