Internal Flow Modelling of Vortex Throttles

Abstract

A finite difference computer code has been used to predict highly swirling confined incompressible turbulent flow in vortex throttles. As turbulence can become highly anistropic in such flow cases, both the widely used two-equation k-ɛ model and a Reynolds stress model have been used. The results have been compared with basic experimental data and the predicted flow structure within the throttles is related to the main design parameters. It has been found that the pressure drop across the vortex throttles occurs mainly through the axial port by dissipation of the high tangential velocity. Energy loss in the vortex chamber tends to reduce the vortex strength, lowering the tangential velocity and consequently reducing the pressure drop.