Performance of a hypersonic twin-nozzle system

Low stagnation temperature of flow allows the most efficient control through the secondary nozzle of a hypersonic planar twin-nozzle system. A cold secondary jet, which seems to act like a gasdynamic wall due to its locally higher acoustic impedance, controls the primary jet channel shaping. Subsonic gas injection helps in stabilizing the flowfield, when pressure ratio is 10 or less. The study is conducted under systematic variations of the stagnation state and the dimensions of the secondary nozzle.