Turbulent uniformity fluctuations in automotive catalysts – A RANS vs DES assessment

Attaining sufficient flow uniformity in catalytic aftertreatment systems is a major challenge for the automotive industry. Computational fluid dynamics (CFD) simulations offer means of analyzing and quantifying this silico. In work, predictions from numerical obtained using conventional steady-state Reynolds-Averaged Navier-Stokes (RANS) approach are contrasted against comprehensive Detached Eddy Simulations (DES) where large-scale turbulence resolved space time. It shown that DES provides access to data on fluctuations could be significant catalyst light-off behavior. However, computational cost approximately three orders magnitude larger than corresponding RANS simulation.