High-enthalpy expansion tube experiments with gas injection

An experimental study was conducted to develop a system for superorbital hi gh-enthalpy pow simulation with gas injection. The expansion tube X-2 was u sed as the base facility. The synchronization of the gas injection to the e xpansion tube operation and the effect of the gas injection on the high-ent halpy flow generation performance are carefully discussed. When hydrogen wa s injected, the performance of the acceleration tube operation was not degr aded, whereas with nitrogen injection the shock speed was significantly dec reased. Hypersonic shock layers with gas injection were visualized by the s chlieren method. This system is expected to be used as a tool to simulate a hypersonic shock layer with ablation for a reentry capsule.