Correlation between hypermixer and fuel injection locations

An experiment was conducted to understand the relation between a wall-mounted alternating-ramp-wedge type hyper mixer and transverse injectors with two different injection locations in a supersonic flow. Three experimental techniques, such as a schlieren visualization, a gas-sampling method, and a stereoscopic particle image velocimetry, were employed to study flowfield having velocity components and vortex structures induced by the interaction between the hyper mixer and the transverse injections, and also to compare the difference of mixing performance of the hyper mixer driven by the different injection location. For normal 1 injection case, an injection hole is located under the compression wedge, so injected helium is immediately impinged on the wedge and widely spread downstream, leading to enhancing mixing performance and holding helium in the mixing layer. On the other hand, for normal 2 injection case, helium is injected downstream of the hyper mixer, thus two flow structures created from the hyper mixer and the transverse injection interact with each other; as momentum flux ratio is increased, the flow structure from the transverse injection plays a significant role on the mixing region, and plenty of helium is penetrated into the supersonic flow.