Turbulent Viscosities for Swirling Flow in a Stationary Annulus

Abstract

Developing axial and decaying tangential velocity fields are surveyed in a stationary annulus with a nearly free vortex initial swirl distribution. Isothermal air was used as the working fluid in an annulus with a single diameter ratio (di /d0 = 0.4) and at a single axial bulk Reynolds number of 1.3 × 105 . The annular geometry was selected because the inner and outer wall curvatures yield opposite effects on the swirl turbulence. The discussion is centered on a critical exposure of the data reduction techniques (momentum integrals) for obtaining the radial variations of the axial and tangential momentum diffusivities.