Compound choking of a two-parallel stream through a convergent duct

The choking of dual subsonic streams flowing through a convergent duct in contact has been investigated experimentally and theoretically. The experiment was conducted by using blow-down wind tunnel. The condition, when the dual stream flow choking (compound choking) occurs at the nozzle exit, was explained by one-dimensional analysis of compound sound wave propagation. The experimental results for the condition of compound choking were compared with the prediction from theoretical analysis, and the schlieren optical method using the spark light source has been used to visualize the flowfield.