Quasi-Spherical, Net Power, D-D Fusion Reactor Concept

The advantages for fusion in a spherical geometry have been recognized for decades. Such systems pose particle confinement challenges, at the surface boundaries where cusps exist. Using a modest PIC code we have modeled a hexahedral-magnetic configuration. HTS coils placed on each surface produce a null-B field at the center of symmetry. Cusps losses are supressed electrostatically. Beam injection sustains a small imbalance in the core particle density, producing an electrostatic potential at the center of the device that confines ions. We have analyzed the distribution functions and conclude that the distributions are Maxwellian. Based on the Magneto-Electrostatic Trap design of Yushmanov (1980) the predicted power-balance is Q = 7 for the DD fueled quasi-spherical reactor in a 4-m diameter geometry, producing 100 megawatts of net power. Higher-order magnetic periodicity, for example in a dodecahedron, substantially improves the particle confinement, as well as the prospect for a scalable, naturally formed, high-beta configuration.