Axially Symmetric Laminar Free Mixing With Large Swirl

Abstract

Viscous laminar axially symmetric free mixing with large swirl is investigated by a boundary-layer type of analysis with integral methods. Large swirl generates axial pressure gradients as well as large radial pressure gradients, and therefore alters the streamwise flow. Examples calculated for both incompressible and compressible flow show that the wake may be significantly lengthened by large swirl. However, this effect is shown to be diminished in the compressible case where higher free-stream Mach numbers lead to decreased densities, and to decreased centrifugal effects, decreased radial pressure gradients, and decreased axial pressure gradients. In the limiting special case of small or moderate swirl the results agree with those previously obtained by Steiger and Bloom [1] in analysis wherein the induced pressure gradients were neglected a priori.