Large eddy simulations on the flow driven by a Rushton turbine

Large eddy simulations were performed on the flow in a baffled stirred tank, driven by a Rushton turbine at Re = 29,000. The simulation procedure consisted of a lattice-Boltzmann scheme for discretizing the Navier-Stokes equations, and a force-field technique for representing the action of the impeller on the fluid. The subgrid-scale model was a conventional Smagorinsky model with a Smagorinsky constant c(s) = 0.12. The uniform, cubic computational grid had a size of about 6 x 10⁶ nodes. The computer code was implemented on a parallel, shared-memory computer platform. The results on the phase-resolved average flow, as well as on the turbulence characteristics, are compared with phase-resolved experimental data. The trailing vortex structure in the vicinity of the impeller was well represented by the simulations.