Shear layer development and entrainment of a jet in supersonic crossflow

A sonic nitrogen jet is injected into a Mach 1.75 supersonic air crossflow at momentum flux ratios between 1 and 5.5. The jet spreading and shear-layer development is quantified via velocity and scalar concentration measurements using Particle Image Velocimetry and Nano-Particle-Based-Laser-Scattering. Jet penetration, trajectory and spreading is assessed as a function of the momentum flux ratio. Jet spreading is compared to Taylor's classical, incompressible dispersion law. The velocity field is analyzed to obtain the mean and RMS velocity profiles in the jet wake and correlated to the species concentration profiles. These results establish the baseline entrainment characteristics that will be revisited for different gases and reacting flows in the near future.