Electric propulsion device for high power applications

A Hall Effect Thruster (HET) electric propulsion device having an anode and a cathode, the propulsion device comprising:

• a discharge annulus having the anode adjacent an end region thereof;
• at least one inlet aperture adjacent the anode, the at least one inlet aperture having propellant gas flow therethrough into the discharge annulus, the propellant gas having a first ionization potential;
• opposed, concentric dielectric walls defining the annulus, at least one of the opposed dielectric walls having pores therein, the pores having cooling gas flow therethrough into the discharge annulus and substantially adjacent the at least one of the opposed dielectric walls, the cooling gas having a first ionization potential higher than the first ionization potential of the propellant gas, the cooling gas adapted to substantially prevent at least one of secondary electron emission and sputtering of the dielectric walls, wherein the cooling gas substantially thermally insulates the at least one of the opposed, concentric dielectric walls;
• and
• an electromagnet operatively disposed in the device such that a magnetic field generated thereby is substantially normal to a center axis of the discharge annulus, the magnetic field having its peak magnitude substantially adjacent an exit plane of the discharge annulus.

An electric propulsion device having an anode and a cathode, the propulsion device comprising:

• a discharge annulus having the anode adjacent an end region thereof;
• at least one inlet aperture adjacent the anode, the at least one inlet aperture adapted to have propellant gas flow therethrough into the discharge annulus, the propellant gas having a first ionization potential;
• and
• opposed, concentric dielectric walls defining the annulus, at least one of the opposed dielectric walls having pores therein, the pores adapted to have cooling gas flow therethrough into the discharge annulus and substantially adjacent the at least one of the opposed dielectric walls, the cooling gas having a first ionization potential higher than the first ionization potential of the propellant gas, the cooling gas adapted to substantially prevent at least one of secondary electron emission and sputtering of the dielectric walls.