Swirling Jet Flow Research Articles

The prediction of turbulent swirling jet flow

A space marching integration procedure is used to solve the Reynolds equations governing the axisymmetric incompressible turbulent swirling jet flow. Turbulence is modelled by the k− ε model with an isotropic turbulent viscosity. Besides mean velocity field, turbulent properties—such as Reynolds stresses, turbulent kinetic energy and dissipation rate—are obtained and the results are compared with experimental data. Agreement is quite encouraging and shows that the assumption of isotropic turbulent viscosity seems plausible.

Inverse Analysis of Turbulent Weakly Swirling Jets

I the development of turbulence models for complex flow systems, turbulent swirling boundary layers provide a convenient testground. Their equations contain two components of turbulent stress rrz and rre, which may be replaced in terms of their associated components of turbulent viscosity Hrz and pa. These must be specified by a turbulence model prior to the prediction of time-mean velocity and pressure in the flowfield. Recent experimental, inverse, and prediction studies have tried to assess the effect of swirl on these components, and have disputed the isotropy assumption that the /^-viscosity number ore = n,rz/ fjLr6, is equal to unity.' The present work obtains expressions for these components directly from analytical operations being performed on fittedcurve spatial distributions of time-mean values in swirling jet flows, so paralleling an associated numerical inverse technique,' and bringing new evidence on the swirl flow turbulence problem.