Characteristic of Capacitive Coupled Radio-frequency Discharge in Supersonic Flow

Aiming at the scientific problem of how to produce the uniform and stable supersonic flow non-equilibrium plasma, and in order to further explore the characteristics of capacitively coupled radio-frequency (CCRF) discharge in supersonic flow, we established a supersonic non-equilibrium ionization MHD technology experiment system to experimentally research the CCRF discharge characteristics for the main flow and boundary region in Ma=3.4 supersonic flow. Moreover, aiming at the problem of real-time diagnosis of supersonic plasma, we established a diagnostic model based on the homogeneous radio-frequency discharge model coupling with power balance equation to diagnose the mean electron number density and electron temperature. The result shows that the uniform and stable plasma can be produced in the supersonic flow by CCRF; the number density of molecules is the main influential factor of characteristic of discharge in supersonic flow, and the supersonic flow has slight effect on the mean electron temperature and is approximately 0.46 eV.