Building proper invariants for subgrid-scale eddy-viscosity models
Document typeConference report
Rights accessRestricted access - publisher's policy
Since direct simulations of the incompressible Navier-Stokes equations are limited to relatively low-Reynolds numbers, dynamically less complex mathematical formulations are necessary for coarse-grain simulations. Eddy-viscosity models for Large-Eddy Simulation is probably the most popular example thereof: they rely on differential operators that should be able to capture well different flow configurations (laminar and 2D flows, near-wall behavior, transitional regime...). Most of them are based on the combination of invariants of a symmetric second-order tensor that is derived from the gradient of the resolved velocity field. In the present work, they are presented in a framework where all the models are represented as a combination of elements of a 5D phase space of invariants. In this way, new models can be constructed by imposing appropriate restrictions in this space. The performance of the proposed models is successfully tested for a turbulent channel flow.
CitationTrias, F. X., Folch, D., Gorobets, A., Oliva, A. Building proper invariants for subgrid-scale eddy-viscosity models. A: European Turbulence Conference. "15th European Turbulence Conference 2015, August 25-28th, 2015, Delft, The Netherlands: proceedings". Delft: 2015.