The Dynamics of Thin Liquid Films in Rotating Tubes: Approximate Analysis

Abstract

The dynamics of a thin liquid film flowing through a pipe rotating about an axis perpendicular to the pipe axis are studied. Static pressure is assumed constant along the pipe and the axial flow of the film is a direct consequence of the pull of the centrifugal force. The film is pushed to one side of the pipe by a Coriolis force which is nonconservative. As a result, a secondary motion is set up in the plane normal to the pipe axis. An approximate set of equations governing the secondary flow is analyzed through an integral technique for the case of a laminar film dominated by viscous effects. A visualization experiment is carried out and the approximate theory is found to compare favorably with the qualitative observations.