Experimental and theoretical investigation of an inverse-pinch coaxial pulsed plasma thruster

The theoretical optimization of an inductively-driven inverse-pinch coaxial pulsed plasma thruster is examined by utilizing and enhancing the magnetohydrodynamic computer code MACH2 with a new circuit model. The simulations show that substantial gains in thrust efficiency can be achieved if circuit design assures that the propellant temperature always remains below the effective decomposition temperature. Concurrently, the experimental efforts with a inverse-pinch coaxial PPT have concentrated on obtaining an axisymmetric discharge in accordance to theoretical optimization. Two ignition schemes have been investigated consistently exhibited that magnetic field variations in the azimuthaf direction are substantial in very low background pressure operation. Alternatively, discharge images of experiments performed with elevated background pressure (>1 mT) show an azimuthally-uniform current discharge on a consistent basis which can serve as guidance toward higher initial density spark-plugs.