1997 年 45 巻 525 号 p. 564-574
The instabilities of confined, supersonic, double shear layer flow are examined in order to develop a mixing enhancement scheme in two-dimensional flow configuration. It is shown that flow confinement is essential to produce the skew-symmetric mode of instability wave which is responsible for rapid mixing in the subsequent nonlinear evolution stage. The linear stability analysis provides a design tool with which suitable flow configuration can be selected. Direct numerical simulation demonstrates that hydrogen gas slowly issued in between supersonic air streams menders, accelerates to supersonic speed and mixes with the air quickly without shock generation, thus leading to explosive combustion. The underlying new physics are explored.