Hi all,

I am doing a simple open channel flow simulation, with shear defined by the log law as the bottom boundary. The domain was descritized with a finite volume staggered grids. When test filtering for the Dynamic LES SGS, particularlly at the bottom boundary for the terms |S|Sij, what boundary conditions do we provide to close the equations?

If you do not resolve the viscous and buffer layer, you need to be careful with the kind of boundary conditions that you employ for the model. I would suggest you to search for review articles on LES by Moin. He has a detailed discussion on the implementation of the BC.

Thank you Harish for the reply. Can you provide me with the reference/paper title that you meantioned? thank you in advance.

@article{moin2002ale, title={{Advances in large eddy simulation methodology for complex flows}}, author={Moin, P.}, journal={International Journal of Heat and Fluid Flow}, volume={23}, number={5}, pages={710--720}, year={2002}, publisher={Elsevier} }

@article{cabot2000awb, title={{Approximate Wall Boundary Conditions in the Large-Eddy Simulation of High Reynolds Number Flow}}, author={Cabot, W. and Moin, P.}, journal={Flow, Turbulence and Combustion}, volume={63}, number={1}, pages={269--291}, year={2000}, publisher={Springer} }

Harish,

thank you very much. I will look into both the papers.