Investigation of Particle-in-Cell Acceleration Techniques for Plasma Simulations

COLISEUM 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 interactions with the surfaces is possible. In order to improve the computational performance of the Particle-in-Cell scheme with Direct Simulation Monte Carlo collision modeling (PIC-DSMC) within COLISEUM, AQUILA, acceleration techniques have been developed that significantly decrease the amount of CPU time needed to obtain a steady-state solution. These techniques 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. Results show that the subcycling acceleration scheme does accurately capture the macroscopic flow properties (such as particle counts and species number densities) and the velocity distributions in the lower density regions of the flow field. However, the higher density regions of the flow field (such as in the main beam of the plasma source) show significant differences that are believed to be associated with the simplifying assumptions used in the original collision modeling scheme within the PIC-DSMC module AQUILA

Outgassing Characterization of Rod Heaters Used for GOES-R Thermal Vacuum Testing

This talk summarizes experimental effort to characterize the outgassing rate of rod heaters (Watrods) used for GOES-R thermal vacuum testing. QCM data obtained with unbaked rods indicated that the outgassing exceeded the allowable budget. We then pre-baked the watrods for 16 hours at ambient pressure and determined that pre-baking reduced the amount of outgassed material by a factor of 4

Erarbeitung von Entscheidungshilfen fuer die TA Luft Nr. 2.2.1.3 (Sonderfallpruefung) - Schadstoffe fuer die keine Immissionswerte festgelegt sind

With 19 refs., 7 tabs., 7 figs.SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman