LES of Separated Flows at Moderate Reynolds Numbers Appropriate for Turbine Blades and

Unmanned Aero Vehicles

Francois Cadieux (USC), Taraneh Sayadi

(CTR), J. Andrzej Domaradzki (USC)

and Sanjeeb Bose, Curtis Hamman

Test bed: DNS database of Spalart and Strelets, JFM 403, 2000; mesh size about 15 million points implying LES resolution target O(105)

Our goal: assess LES capabilities to reduce computational requirements for simulating separated flows significantly, to O(1%) of DNS resolution, typical of LES of turbulent flows

First two weeks: Performed LES and no-model simulations for the dynamic model with 4.4% of DNS resolution

displacement thickness

momentum thickness

Cp

Cf

Last two weeks: To have one-to-one comparison full DNS is currently run with 4x Spalarats

resolution (Nx = 1536, Ny = 300, Nz = 128; x+ = 10, y+ = 0.5, z + = 8) Investigate transition in the shear layer above the bubble and turbulence

behind the bubble where LES does not match DNS data Implement and evaluate additional SGS models developed at USC Encourage other participants to apply their programs/models to this simple and

well documented problem