Three-dimensional modeling of an ideal nozzle for advanced propulsion

Advanced propulsion systems such as pulsed fission and fusion rockets hold the potential for opening up the solar system in ways few other propulsion technologies can. The University of Alabama in Huntsville is exploring one such concept in the form of pulsed z-pinch fusion propulsion. One of the technical hurdles to utilizing any pulsed fusion concept is the conversion from an isotropic expansion of a plasma into directed motion to produce thrust. This thesis investigates three dimensional modeling of pulsed nozzle performance in which the initial gas is a cylindrical gas column, emulating the initial conditions found in pulsed plasma discharges common in fusion experiments. Two nozzle geometries were investigated, a pusher plate and a hemispherical nozzle.;Simulations of these systems were conducted using SPFMax, a recently developed smoothed particle hydrodynamics code (SPH). The SPH method was chosen because it is naturally adaptive and accurate for resolving the vacuum/gas boundary which always exists in pulsed fusion systems. Argon plasma was used to compare the two systems to determine which offers better performance. The plasma was also subjected to a wide variety of shapes and initial conditions to determine what would offer higher performance for the two systems.