Turbulent Shear Flows 8 pp 169-187 | Cite as

# Large-Eddy Simulation of a Turbulent Flow with Separation

## Abstract

Large-eddy simulations of the fully-developed, turbulent channel flow over a rearward-facing step are presented and discussed. Predicted mean-flow quantities of the high Reynolds number flow compare well with the results of experimental investigations of the same flow. A momentum balance including all the terms appearing in the Reynolds-averaged Navier-Stokes equations demonstrates the importance of the stress terms in the separation and reattachment regions of the flow. Spectra taken from time series of the fluctuating pressure reveal the presence of low-frequency motion in the recirculation zone. Similar behavior has been observed in experimental studies of separated flows occurring in a variety of geometries. Finally, the instantaneous flow field is analyzed for the presence of topological flow patterns typical for turbulent shear flows. To what extent such events contribute to the statistical properties of the flow is discussed.

### Keywords

Vortex Convection Shrinkage Vorticity Hunt## Preview

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