Ehsan Baniasadi, Ahmad Sedaghat, Stability of flow between two eccentric cylinders With heat transfer and rotation, 11th Fluid Dynamics Conference, May 2008 K. N. Toosi University of Technology,

11^th Fluid Dynamics Conference, May 2008

K. N. Toosi University of Technology, Faculty of Mechanical Engineering

Stability of flow between two eccentric cylinders

With heat transfer and rotation

Abstract: The effect of a radial temperature gradient on stability of steady-state flow of a viscous liquid between two solid eccentric cylinders with inner one rotate in determined velocity was investigated. The existence of hydrodynamic instabilities leads to formation of Taylor vortices in flows in the annulus between two cylinders. The study of heat transfer within the rotating enclosure is complex. For horizontal configuration, the buoyancy and the centrifugal effects (created by the heated rotating cylinder) give rise to fully three-dimensional flows.           

       Understanding the dynamics of these flows is of great practical interest because they are encountered in many engineering and geophysical problems, and it may help to improve mass and heat transfer involved in different processes, e.g. cooling of rotating electrical machinery and turbines rotors or to explain some dynamical processes in the oceans and the atmosphere.

      The linear stability problem is considered in the Boussinesq approximation and the results of 3D numerical analysis of flow and heat transfer in two horizontal eccentric cylinders with a heated rotating inner cylinder are presented. Solutions are presented for a number of Taylor and Reyleigh numbers.

Keywords: hydrodynamic instability ,Taylor vortex,centrifugal forces, viscous heating ,eccentricity