An Approach to Calculate Leakage Flow, Stiffness and Damping of Annular Seals in Turbulent Flow Using Lubrication Theory, Part I: Analysis

Abstract

This paper presents a general theoretical approach to evaluate the leakage flow, stiffness and damping of annular seals in turbulent flow regime including fluid inertia using turbulent lubrication theory. Fluid inertia effect has been incorporated by perturbing the pressure and fluid velocities following the procedure cited in the literature for laminar flow. Turbulent lubrication theory based on eddy viscosity model has been followed to develop turbulent Reynolds equation. Perturbation theory for small amplitude vibration of the journal center has been followed to determine stiffness and damping of the seal. Theoretical analysis presented is general and seal geometry effect can be incorporated through film shape description.

Keywords

• turbulent lubrication
• leakage flow
• seal forces
• stiffness
• damping
• annular seal