OPTIMIZATION OF AN IEC FUSION DEVICE TO INCREASE STEADY-STATE D-D NEUTRON GENERATION RATES

The University of Wisconsin-Madison Inertial Electrostatic Confinement (IEC) Fusion Research Group has been performing experiments on an IEC device known as HOMER. This device is a 65cm high, 91cm diameter cylindrical aluminum vacuum chamber that contains two concentric spherical wire grids, the outer grid acting as the anode and the inner grid as the cathode. The potential difference between the anode and cathode drives ions towards the center of the grids. Using this device, steady-state D-D fusion reactions are created in order to produce 2.45 Me V neutrons. With the goal of achieving maximum neutron production rates, the following parameters have been varied: cathode voltage, ion current, operating pressure, and the separation distance between the anode and cathode. The studies on pressure, voltage, and current have led to the discovery of trends that allow for the extrapolation of neutron rates at various conditions. The cathode/anode separation studies have offered valuable insight into how the distance between the electrodes effects the concentration of deuterium molecular ions and the ion energy spectra, and has led to the implementation of a configuration that better maximizes neutron production rates.