| The principal objective of the dissertation is to explore the theoretical feasibility of the coaxial plasma accelerator as a candidate driver for magnetized target fusion (MTF) by the use of detailed 2-D magnetohydrodynamics modeling studies. MACH2, a 2-D magnetohydrodynamic code, was the primary computational tool for this study. We found that incorporating the appropriate physics models is critical in getting good agreement with experimental results. We modeled plasma liner formation and implosion of a magnetized plasma by twelve plasma jets to put the remaining study in a magnetized target fusion context. The results show that the magnetic flux is compressed with the target, and the magnetic field suppresses the cross-field thermal conduction losses.; Assuming that the working plasma satisfies a proposed set of microphysics conditions that might enhance the likelihood of accelerating the plasma as a "slug," the macrodynamics of accelerating the plasma in a standard, conventional coaxial plasma gun was systematically studied with respect to the driving current, mass distribution, initial plasma temperature, and electrode dimensions with the help of the 2-D MHD MACH2 code. The 2-D MHD modeling identifies a dynamical instability, which we called the "blowby" instability, that limits the performance. Density profile, ratio of electrode radii, initial jet length were found to be important in determining the onset of the instability.; Guided by the 2-D modeling results, a plasma accelerator point design was proposed and studied. The modeling study shows that the blowby instability could be suppressed through appropriate shaping of the electrodes and plasma injection to induce a favorable density profile and an initial canting of the current sheet with the leading edge along the outer electrodes. With only four cases investigated, the desired performance objectives were reached. With further adjustments and/or alternate geometries, greater success and better accelerator performance can be expected. |
