Session KP01 - Poster Session III.
POSTER session, Tuesday afternoon, March 23
Exhibit Hall, GWCC
The spherical Inertial Electrostatic Confinement (IEC) device produces neutrons from the fusion of an electrostatically confined deuterium plasma. Charge-exchange collisions are an important energy sink in this fusion plasma. During these collisions, fast become high-energy neutrals, leaving behind thermal energy ions. These resulting thermal ions re-gain some energy due to the local accelerating potential field. Still, the collisions represent a net transfer of energy from ions to neutrals, decreasing the fusion rate and the efficiency of the system.
A computer model of charge exchange in a spherical IEC device was developed to describe the effects of voltage, pressure, and cathode radius on the process, and hence on the fusion rate. The results indicate that a significant fraction of charge-exchange collisions occur at low energy. When the re-acceleration of thermal ions is taken into account, the ion population retains, on average, 70-80 their initial potential energy. Results yield a fusion scaling with cathode radius that generally matches experimental results. This information is important for the design of future, high-yield, IEC fusion neutron sources.