Numerical Investigation of Turbulent Mixing in a Jet/Wake Vortex Interaction

Abstract

A three-dimensional temporal numerical simulation of the interaction between a jet and a vortex wake is described to contribute to the understanding and modeling of engine jet dispersion of an aircraft in cruise condition. First, a comparison of the numerical results with a wind-tunnel experiment is presented. Experimental data comprise turbulent rates measured by a laser Doppler velocimeter and mean temperature e elds delivered by thermocouples. Thecalculation isin quite good agreement with the experiment. Second, the passivescalar distribution (initially included in the jet )in the vortex wake is focused on. The turbulence induced by the jet e owe eld interacts with the vortex, resulting in large-scale structures generated outside the vortex core, whereas the region very close to the core keeps its laminar state. The passive scalar concentrates in the large-scale structures where azimuthal and axial (positive and negative ) vortices are combined. The resulting scalar e eld distribution shows no scalar inside the vortex core.