Development of a new method for fuel mixing enhancement in a scramjet engine

为了提高超燃冲压发动机的燃油混合性能，提出了一种新的燃油混合方法。该方法基于利用空腔诱导流动振荡的方法。改进了空腔的几何形状，从而产生三维流场。这种三维流动有利于混合增强。为了模拟燃料喷射，将含有少量丙酮的氮气喷入超音速流中。注入气体的混合是可视化的激光诱导丙酮荧光。结果表明，改进型腔的混合增强作用比传统矩形腔的混合增强作用更强。

In order to enhance the fuel mixing in a scramjet engine, a new method of fuel mixing is suggested. This method is based on the method in which cavity-induced flow oscillation is utilized. The geometry of the cavity is improved so that the three-dimensional flow field is produced. This three-dimensional flow advantages the mixing enhancement. In order to simulate the fuel injection, the nitrogen gas which contains a small amount of acetone is injected into the supersonic flow. The mixing of the injected gas is visualized by the laser-induce acetone fluorescence. As a result, the mixing enhancement by the improved cavity is found to be stronger than that by the conventional rectangular cavity.