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A model for plasma confinement is developed and applied for describing an electrically confined thermonuclear plasma. The plasma confinement model includes both an analytical approach that excludes space charge effects and a classical trajectory Monte Carlo simulation that accounts for space charge. The plasma consists of reactant ions that form a non-neutral plasma without electrons. The plasma drifts around a negatively charged electrode. Conditions are predicted for confining a deuterium–tritium plasma using a 460 kV applied electric potential difference. The ion plasma would have a 20 keV temperature, a 1020 m−3 peak density, and a 110 keV average kinetic energy per ion (including drift and thermal portions at a certain point in the plasma). The fusion energy production rate is predicted to be 10 times larger than the energy loss rate, including contributions associated with both plasma loss to electrodes and secondary electron emission. However, an approach for enhancing the fusion power density may have to be employed to realize a practical use for centrifugal-electrostatic confinement fusion.
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Preliminary Characterization of an Iodine Plasma Source for use in Material Analysis
Electric propulsion devices using xenon as a propellant are a high efficiency solution for large conventional satellites. The high storage density of iodine would enable these devices to require less mass for use in space technologies, if used as a propellant as an alternative to xenon. The ability to reduce the mass required for electric propulsion devices would not only reduce costs of space travel but also open up new opportunities for these devices to be used in smaller, more volume constrained missions. Iodine is a strong oxidizing agent. To determine if it is a viable alternative, the erosive properties must be quantified. The object of this research project was to characterize an iodine plasma source before using it for material exposure and analysis. A double Langmuir probe was used as the method of data acquisition for the plasma conditions. The plasma characterization identified the conditions in the plasma source that will be used to properly quantify the erosive properties in iodine plasma. Preliminary results indicate a maximum electron temperature of four electron volts, and a maximum plasma density of eight inverse cubic centimeters.
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- Award ID(s):
- 1655280
- PAR ID:
- 10232064
- Date Published:
- Journal Name:
- 72nd Annual Meeting of the APS Division of Fluid Dynamics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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