Numerical simulation of jet mixing enhancement using rectangular control jets

Abstract

The effect of rectangular control jet on the mixing of round jet with ambient air was studied numerically, in the present work. The effect on the length of main jet potential core and the penetration depth of the control jet, due to variations in velocity and width of the control jet, was studied. The mechanism of jet mixing enhancement was also studied. The results indicated that due to the rectangle jets, the main core region was bifurcated. Thus, there were two definitions for the length of main jet core: the length of centerline potential core and the length of actual potential core. Both lengths decreased with increase in control jet velocity. Besides, the length of the actual potential core decreased with increase in control jet width. However, for the length of centerline potential core, there was a specific width, at which the length of centerline potential core reached a minimum value. Finally, the deformation of the main jet was a factor, more critical compared to the streamwise vortices, which had an effect on the control jet.