Modelling and Simulation of Fluid Flow and Heat Transfer in Rotor-Stator Disc System

Abstract

The focus of present work is to investigate the fluid flow and heat transfer behaviour in the rotor-stator disc flow system for the range of mass flow rates 2530≤Cw 9680 and a fixed value rotational Reynolds number Re=1.25×106 . The predictions have been obtained through a finite-difference, axisymmetric, steady-state and elliptic method, in the cylindrical polar co-ordinate system. A CFD commercial code Fluent has been implemented by provoking the two turbulence models, the low Reynolds number k-ε and the low Reynolds number second moment closure models. The predictions show the basic characteristics of the fluid flow and heat transfer in the rotor-stator system for the range of mass flow rate. For a lower mass flow rate, a strong recirculating core of fluid was produced, which formed the axial-wind between the two discs, consequently heat is transferred from hot rotor disc to air and then to the stator. For a higher mass flow rate a strong wall-jet was predicted along the rotor disc, result of that maximum heat is transferred in the outer region of the cavity. The predicted flow structure, temperature field and the Nusselt numbers show the basic characteristics of the rotor-stator disc flow system. A comparison of the computed Nusselt numbers shows a good level of agreement with the measurements. The predicted results provide the essential information about the windage heating and thermal growth in the rotor-stator disc spaces.