DNS / LES of Complex Turbulent Flow Over Bluff Bodies and Wind Turbine Blades

Details

We are funded under an OCRF CRG-1 grant to compute the complex turbulent flow over bluff bodies and wind turbine blades. This is in joint collaboration with Caltech, Colorado State University and LLNL. As part of the research we have undertaken DNS and LES of flows over airfoils.

The laminar-turbulence transition for flow over an airfoil at Re =10,000 with 10 degrees angle of attack is investigated using the direct numerical simulation (DNS) method. Our in-house code is based on an energy conservative fourth-order scheme (Morinishi et al. JCP 1998). The code is parallelized with standard MPI-protocol and all simulations are performed on an IBM Blue Gene/P supercomputer Shaheen at KAUST. It requires about three million core-hours for one simulation. In addition to DNS we are developing an incompressible LES code in the general curvilinear coordinates, in which the SGS model follows the concept of the stretched-spiral vortex (SGS) model originally developed by Professor D. I. Pullin in Caltech. Further, a wall model in complex geometry is in process, in which the wall shear stress is governed by an ODE based on wall-filtering and averaging of the streamwise momentum equation.

Collaborators

Caltech, Colorado State University and Lawrence Livermore National Laboratory