Near-field interaction of a jet with leading-edge vortices

Results of the interaction between the vortex-wake of a 75-deg leading-edge sweep delta wing and a circular jet issuing from a tube parallel to the ce nterline of the wing are presented. Laser lightsheet flow visualizations an d total pressure measurements were used to characterize the flowfield. In a ddition, a vortex-filament model used to supplement the examination of the streamwise evolution of jet exhaust in the presence of trailing vortices wa s shown to provide a reasonable qualitative description of the observed flo w behavior. Visualization and total-pressure data revealed that introductio n of large-scale persistent streamwise vortices substantially augments the jet spreading. Moreover, such an occurrence can be achieved within a short distance downstream.