Abstract: A plasma electrothermal thruster includes a capillary passage in which a plasma discharge is formed and directed out of an open end of the passage into a supersonic nozzle. Liquid supplied to the capillary passage becomes partially atomized to cool a confining surface of the passage. The plasma discharge is formed as the atomized liquid flows out of the open end into a supersonic equilibrium nozzle. The discharge can have a duration greater than the two way travel time of acoustic energy in the capillary to cause the plasma to flow continuously through the nozzle during the time of the discharge pulse.

Abstract: A projectile is accelerated through a gun barrel bore by a cartridge containing a high temperature, high pressure plasma jet source. The cartridge has a geometry enabling it to be loaded into a breech bore of the gun. The plasma jet is supplied to the rear of the projectile and is derived by a tube having an interior wall forming a capillary passage. A discharge voltage applied between spaced regions along the capillary passage ionizes a dielectric to form a plasma. First and second ends of the passage are respectively open and blocked to enable and prevent the flow of plasma through them. The blocked end closes the breech bore.

Abstract: A pulse forming network, responsive to a DC power supply, supplies predetermined current waveforms to a load in response to commands from a programmed source. Plural inductors are connected to switches responsive to commands from the programmed source. The switches are controlled to couple the inductors to the DC source to charge the inductors to a predetermined current level that is maintained substantially constant. The predetermined current level in each inductor is supplied to the load by switches controlled by the programmed source so that during successive intervals the predetermined constant current levels from differing numbers of the inductors flow from the inductors to the load. The inductance of each inductor, the load impedance and the duration current is supplied to the load by the inductors are such that the predetermined current level supplied by each inductor to the load is maintained relatively constant.

Abstract: A projectile is accelerated along a confined path by supplying a pulsed high pressure, high velocity plasma jet to the rear of the projectile as the projectile traverses the path. The jet enters the confined path at a non-zero angle relative to the projectile path. The pulse is derived from a dielectric capillary tube having an interior wall from which plasma forming material is ablated in response to a discharge voltage. The projectile can be accelerated in response to the kinetic energy in the plasma jet or in response to a pressure increase of gases in the confined path resulting from the heat added to the gases by the plasma.