Experiments were conducted in the intake model with 0%, 15% and 21.67% blockages. After starting the wind tunnel, the cowl was rotated from complete opening position to close and returned back. The flow was visualized by Schlieren technique. It is understood from the above experiments that unstarted intake because of back pressure rise can be restarted by the movement of cowl. Started intake can also be made start off design. When cowl is moved back, hysteretic phenomenon presents in start on design, start off design. At higher mass capture ratio, shock oscillations were found along the ramp surface outside the cowl lip, between inside and outside the cowl and inside the cowl before intake starts.
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