Simulation of turbulent mixing layers
Abstract
A hybrid numerical scheme, combined with a scalar convection scheme, is used to compute turbulent mixing layers. The hybrid scheme is used to solve the vorticity equation by dividing the domain into two regions, applying a Lagrangian method in one region and an Eulerian method in the other. The scalar convection scheme is used to track an interface which separates a dyed fluid from a dyefree fluid, thereby distinguishing the fluid that starts on the high speed side from the fluid that starts on the low speed side. A twodimensional mixing layer has been simulated using this new method; the roll up of a vortex sheet into structures that interact and pair is observed. The growth of the momentum thickness and the development of the mean turbulence statistics are found to be consistent with experimental observations. Forcing of the layer at moderate and low frequencies shows a dramatic effect on the growth of the momentum thickness and the entrainment ratio. Low frequency forcing enhances the growth of the layer; moderate frequency forcing inhibits the growth.
 Publication:

5th Symposium on Turbulent Shear Flows
 Pub Date:
 1985
 Bibcode:
 1985stsf.proc....3M
 Keywords:

 Computational Fluid Dynamics;
 Mixing Layers (Fluids);
 Shear Layers;
 Turbulent Boundary Layer;
 Turbulent Mixing;
 Two Dimensional Boundary Layer;
 EulerLagrange Equation;
 Flow Velocity;
 Fluid Boundaries;
 Vortex Sheets;
 Vorticity Equations;
 Fluid Mechanics and Heat Transfer