Interaction of a cylindrical beam with a surrounding annular fluid

Abstract

Added mass and damping factors for lateral vibrational motion and precessional (whirl) motion of a cylindrical beam, surrounded by a viscous fluid annulus, are obtained in the first approximation by solving the linearized Navier-Stokes equations in a two dimensional flow field. The dynamic responses of the cylindrical beams are then predicted analytically. Results of some experiments on simply supported and free-free beams excited by a lateral harmonic driving force are compared with theoretical prediction. Forced response of well-casings surrounded by cement-slurry is determined theoretically. The response parameters so obtained are compared with those required for fresh-concrete consolidation available in the literature. Further, the forces, and hence vibrators that can generate these casing-response parameters are specified.