A pulsed plasma torch and its performance in a Mach 2.5 supersonic flow

Characteristics of torch plasma that is intended as an ignition aid within a scramjet engine are studied in a Mach 2.5 wind tunnel. This torch system, with its high-voltage discharge between the electrodes of a torch module, is operated in pulsed mode. The plasma jet generated by this torch module is diagnosed by the discharge power and through imaging of its plume in a quiescent environment and in a supersonic crossflow. This torch can deliver up to 100 J in each pulse. Within the Mach-2.5 supersonic flow, which approximates the scramjet-engine startup condition, the penetration height and the volume of torch plume into the crossflow are determined.