An experimental investigation on the asymmetric evolution of a lobed jet flow

This paper presents an experimental investigation of a turbulent isothermal air lobed jet flow within an axial distance of thirty equivalent diameters. Lobed jet dynamics is compared to an isothermal axisymmetric jet with same exit Reynolds number. It is showed that the geometrical asymmetry persists within the explored distance, in spite of the presence of a self-preserving region.

In the far field of the lobed jet, this geometrical asymmetry is accompanied by the reduction of the turbulence intensities and of the turbulent shear stress. It is also found that the mixing performance of the lobed jet remains superior to the one of the axisymmetric reference jet for the explored axial range.