Stabilization of combustion front in supersonic flow using streamer’s discharge

Abstract

Thermodynamic analysis shows that for flights with velocities exceeding six sound velocities, it is required to burn fuel not in a subsonic but in a supersonic flow. The aim of this work is to investigate the possibility of creating a stationary combustion front in a supersonic flow by igniting the mixture with an attached microwave discharge. Discharges are created on the resonator by means of a pulsed source of quasi-optical microwave radiation. This method of initiation is one or two orders of magnitude more economical than other known methods of plasma ignition and combustion stabilization. A numerical evaluation and comparison with experiment of the propagation velocity of a subcritical streamer discharge in a stationary medium and in a supersonic drifting flow are performed. Experiments have been conducted to ignite a flat flow of propane-air mixture, as well as ignition of the propane stream fed into the airflow, which simulates the operation of the fuel injector. In all cases, the experiments confirmed a steady fuel combustion, which was controlled by the temperature measurements with a thermocouple.