全流量补燃循环气气燃烧相似性缩尺试验研究

In order to guide the design of chamber injector for full-flow stage combustion engine, reduced-scale test of gas-gas combustion similarity in a chamber with quartz windows was conducted utilizing gaseous oxygen and gaseous hydrogen as propellants. The high-speed camera was used to obtain the combustion flame structure near the exit of the coaxial injector under the stable combustion and unstable combustion, and the frequency characteristics of unstable combustion were analyzed. The results show that, with the types of propellant, propellant temperature, propellant mixing ratio, combustion chamber and nozzle structure size unchanged, by increasing propellant flow rate, the stable and unstable combustion flame structure is similar to some extent, and the frequency of unstable combustion is the same.