Laboratory Modeling of the Plasma Layer at Hypersonic Flight

A simple approach to modeling the plasma layer similar to that appearing in the vicinity of a hypersonic vehicle is demonstrated in a laboratory experiment. This approach is based on the use of a hypersonic jet from a cathodic arc plasma. Another critical element of this laboratory experiment is a blunt body made from a fairly thin foil of refractory material. In experiments, this blunt body is heated by the plasma jet to a temperature sufficiently high to ensure evaporation of surface deposits produced by the metallic plasma jet. This process mimics reflection of gas flow from the hypersonic vehicle in a real flight. Two-dimensional distributions of the hypersonic plasma flow around the blunt body were measured using electrostatic Langmuir probes. Measured plasma density was typically 10(12) cm(-3), which is close to the values measured for real hypersonic flight. The demonstrated laboratory experiment can be used to validate numerical codes for simulating hypersonic flight and to conduct ground-based tests for efficiency validation of various radio communication blackout mitigation techniques.