title: Simulating flow separation from continuous surfaces: routes to overcoming the Reynolds number barrier.
abstract: This paper provides a discussion of several aspects of the construction of approaches that combine statistical (Reynolds-averaged Navier-Stokes, RANS) models with large eddy simulation (LES), with the objective of making LES an economically viable method for predicting complex, high Reynolds number turbulent flows. The first part provides a review of alternative approaches, highlighting their rationale and major elements. Next, two particular methods are introduced in greater detail: one based on coupling near-wall RANS models to the outer LES domain on a single contiguous mesh, and the other involving the application of the RANS and LES procedures on separate zones, the former confined to a thin near-wall layer. Examples for their performance are included for channel flow and, in the case of the zonal strategy, for three separated flows. Finally, a discussion of prospects is given, as viewed from the writer's perspective.
authors.affiliation: Department of Aeronautics, Imperial College London, Prince Consort Road, London SW7 2AZ, UK. mike.leschziner@ic.ac.uk
authors.forename: Michael
authors.initials: M
authors.lastname: Leschziner
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Tessicini