Inertial Electrostatic Confinement (IEC)
The NSD GRADEL FUSION neutron generator is an improvement of the spherical Inertial Electrostatic Confinement (IEC) device. It provides a linear geometry source.
IEC is the simplest way to achieve sustained nuclear fusion. While the possibility to scale the technology up to achieve net power output can be debated, there is no doubt that the technology provides a credible neutron generator without the disadvantages a solid target has.
IEC fusion is briefly illustrated below.
A semi transparent grid cathode (-) is surrounded by an anode (+) at ground potential.
Applying a very high electric field over a low pressure gas will induce a glow discharge.
The positive ions (shown as a red spot) are attracted to the cathode. Ideally, an ion will be channeled by the electrostatic focusing effect to pass through the cathode grid apertures. If there is no collision with other ions and neutral particles, the ion oscillates in the device.
In reality, the low pressure gas-plasma is still very dense so that sufficient collisions of various types will occur. Despite these energy loss mechanisms sufficient ions do get accelerated to kinetic energy levels such that fusion collisions occur. The greater is the applied voltage on the glow discharge, the greater is the probability of a fusion collision.
With increased numbers of ions , charge space effects can have an influence on the ion trajectories in the central volume. The animation below illustrates that a virtual anode forms by the self organisation of the high density ion population. The virtual anode has a positive charge great enough to deflect ions and effectively keep them confined in the central region. These ions contribute their positive charge to the space charge which is self distributing into a shell of positive space charge.
This plasma structure confines the ions at kinetic energies where fusion collisions may occur. The longer confinement time increases the fusion rate more than a straightforward increase of the applied electric current. With pulsed current at high voltage, the super-linear scaling becomes most apparent with much greater neutron emission rates.
Fusion of the hydrogen isotopes Deuterium and/or Tritium produces a charged particle and a neutron. The neutron is able to escape from the reaction chamber.
Note that this process is occurring 106 to 109 times per second in typical NSD GRADEL FUSION neutron generators.