Forces and Moments Due to Misalignment Vibrations in Annular Liquid Seals Using the Averaged Navier-Stokes Equations

This paper presents a method to calculate forces and moments in misaligned annular liquid seals operating in centered position and turbulent flow regimes. The method is based on the numerical integration of the perturbed averaged Navier-Stokes equations so it has the capacity to treat recirculating flows in seal grooves. Due to the analytic coordinate transformation used in deriving the perturbed flow equations, the approach is limited to smooth-rotor seals. The perturbed flow equations are cast in an appropriate form in order to obtain a single expression for eccentric and misaligned seals. The boundary conditions are obtained from the no-slip conditions and from the logarithmic law. Validations of the method are made using the experimental results of Kanemori and Iwatsubo (1994) for a straight seal. Comparisons with other theoretical predictions are also included. Forces and moments in a four-grooves labyrinth seal are discussed.