Experimental and Theoretical Investigation of Three Dimensional Turbulent Mixing in Jets and Ducts

摘要

Only parabolic flows are considered. The model was derived from a two dimensional model, based on a turbulent viscosity concept and the supposition that turbulence can be adequately described by the kinetic energy of turbulence and the dissipation rate of turbulent kinetic energy. Predictions are made for two laboratory model flows with complex-shaped shear layers. A computer program is developed that predicts the flow in an exhaust duct of a fan jet engine equipped with a lobe mixer. The important features of the flow are predicted accurately, even in the region where the shear layers completely fill the flow field where discrepancies are usually quite large.