Prediction of Power-Law Fluid Flow through an Eccentric Annulus with Inner Cylinder in Rotation using k-ω Turbulence Model

ABSTRACT Situation of flow through annular pipe arises in many practical situations like chemical process plants, heat exchangers, hydraulic transport etc. Also it presents a situation of inhomogeneous fluid flow case. Thus it is one of the important problems in fluid mechanics from practical as well as from theoretical stand point. Many situations consider non-Newtonian flows through an eccentric annulus with inner cylinder in rotation. The present investigation focuses on prediction of turbulent flow through eccentric annulus, using standard k-ω turbulence model. A three dimensional orthogonal hexahedral mesh with suitable boundary conditions & input parameters was taken as computational domain for eccentric annulus. This was solved with SIMPLE algorithm and QUICK up-winding scheme. The Reynolds number was taken as 15000 considering the two inner cylinder rotational speeds of 300 rpm and 600 rpm. The results were validated against the published experimental work of Nouri & Whitelaw (1997). Radial velocity, axial velocity and tangential velocity of fluid were plotted along chosen planes and contours of molecular viscosity as well as turbulence kinetic energy were observed. The relative effects of these velocity components were discussed for critical sections of the model so as to have close observation of the various flow situations present over the cross-section.