The three-dimensional supersonic flow and mixing fields with a perpendicular air injection from a finite length slit

This study investigates the supersonic flow and mixing with a perpendicular air injection from a finite length slit experimentally and numerically. A finite length slit means a slit with two ends. Two slit angles of 90 degrees and 45 degrees are examined. The slit angle is an angle between the main flow and the slit length direction. The flow and the mixing are evaluated by the total pressure loss and the mixing efficiency, respectively. The numerical results agree with the experimental ones qualitatively and quantitatively. For the slit angle of 45 degrees, the mixing is enhanced because there is no vortex at the slit ends and the main flow can go through behind the slit smoothly. In addition, for the slit angle of 45 degrees, the loss is reduced because the forward projection area of the slit decreases.