• Dr. Heng Xiao
  • Institute of Fluid Dynamics
  • 221 Randolph Hall
  • 4:00 p.m.
  • Faculty Host: Dr. Alan Brown

Large-Eddy Simulation (LES) has gained successes in the past decades, particularly for free-shear flows.  In wall-bounded flows, however, the computational cost of LES is very high in order to resolve the near-wall features.  This is a major hurdle for the application of LES in industrial and practical flows.

In this talk, I will present a consistent hybrid framework for turbulence modeling.  In this framework, the filtered equations and the Reynolds averaged Navier-Stokes (RANS) equations are solved simultaneously in the whole domain on their respective meshes.  Consistency between the two solutions is achieved through additional drift forcing terms in the corresponding equations.  Compared to current methods in the literature, this approach leads to very clean conditions at the LES/RANS interfaces.  The results demonstrate that the hybrid solver leads to significantly improved results with minor computational overhead compared to traditional LES, making it a promising candidate for industrial flow simulations.  On going development include: (1) coupling with high-accuracy Cartesian LES solvers, (2) application to more complex flow (e.g. flow around cylinder), and (3) using more advanced turbulence models such as Reynolds Stress Transport Models.