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ABSTRACTCOLISEUM is an application framework that integrates plasma propagation schemes and arbitrary 3D surface geometries. Using Particle-in-Cell (PIC) schemes to model the plasma propagation high fidelity modeling of the plasma and its interaction with the surfaces is possible. In order to improve the computational performance of the Particle-in-Cell (PIC) scheme within COLISEUM (AQUILA), accelerate techniques have been developed that significantly decrease the amount of CPU time needed to obtain a stead-state solution. These schemes have been demonstrated to decrease the CPU time from 3 to 24 times with little appreciable differences in the global particle properties and number densities. This work investigates the differences in the local plasma properties that result from the application of the different acceleration techniques. In particular, the number densities and velocity distributions of the ions and neutrals demonstrate that the solution acceleration schemes produce very similar solutions outside the main path of the plasma source. Within the main path of the plasma source the local plasma properties show marked differences that might be associated with the time steps associated with these schemes and/or the collision modeling scheme within AQUILA.
SECURITY CLASSIFICATION OF:17 COLISEUM is a application framework that integrates plasma propagation schemes and arbitrary 3D surface geometries. Using Particle-in-Cell (PIC) schemes to model the plasma propagation high fidelity modeling of the plasma and its interaction with the surfaces is possible. In order to improve the computational performance of the Particle-in-Cell (PIC) scheme within COLISEUM (AQUILA), accelerate techniques have been developed that significantly decrease the amount of CPU time needed to obtain a steady-state solution. These schemes have been demonstrated to decrease the CPU time from 3 to 24 times with little appreciable differences in the global particle properties and number densities. This works investigates the differences in the local plasma properties that result from the application of the different acceleration techniques. In particular, the number densities and velocity distributions of the ions and neutrals demonstrate that the solution acceleration schemes produce very similar solutions outside of the main path of the plasma source. Within the main path of the plasma source the local plasma properties show marked differences that might be associated with the time steps associated with these schemes and...