Four kinds of the two-equation turbulence model's research on flow field simulation performance of DPF's porous media and swirl-type regeneration burner

The flow field of the diesel particulate filter (DPF) with porous media and the swirl regeneration burner is complex, so which kind of turbulence model to be chosen has a great influence on the accuracy and performance on the computational fluid dynamics (CFD) simulation. Based on Fluent software and with the same conditions, the standard k - epsilon RNG k - epsilon, Realizable k - epsilon and SST k - omega turbulence models were adopted to get the back-flow characteristics and the distribution of velocity, pressure and turbulent kinetic energy in the swirl burner and the porous media, then the results were compared and analyzed. It shows that, at the sudden expansion zones and near-wall region, the flow characteristics and back-flow features of the Realizable k - epsilon model are clearer than that of the standard k-e model and the RNG kmodel, and the maximum peaks of turbulent kinetic energy and the larger gradient are gotten by the RNG k - epsilon model, but better back-flow characteristics and more abundant details of flow field by the SST k - omega model, and the center average velocity and pressure at the inlet and outlet all agreed well with experiments. (C) 2015 Elsevier Ltd. All rights reserved.