A Polywell Cusp-Confinement Deuterium Reactor: Wiffle-Ball Beta, Electron Recirculation Losses and Net Balance

This paper presents a complete, computed design study of a fusion power plant based on a polywell cusp device: a cubic arrangement of six ring coils whose fields form point and line cusps around a field-free centre. The fuel is catalysed deuterium, releasing an effective 12 MeV per initial deuterium pair once the tritium and helium-3 products are burned in place. Heating is by electron beam injection maintaining a negative potential well that electrostatically confines ions in a high-beta cusp field, and the blanket concept is water-cooled lithium shield sized for the deuterium deuterium neutron flux, without a breeding requirement. Sizing follows from a zero-dimensional energy balance evaluated in the accompanying computation: fusion power 0.4128 MW, auxiliary heating 95 MW, plasma gain Q 0.00434, neutron power 0.1569 MW, first-wall neutron loading 0.00162 MW per square metre, gross electric output 35.23 MW, recirculating power 167.3 MW and net electric output -132.1 MW. Radiated bremsstrahlung removes 0.21 MW and transport removes 637.8 MW, against alpha-particle self-heating of 0.1857 MW. The plant verdict on the stated assumptions is net negative. Where a quantity depends on an assumption that experiments have not yet demonstrated at the required value, that dependence is stated numerically so that the design can be re-scored as measurements improve. This study is simulated and computed from stated assumptions; it is not a measurement, and no part of the plant has been built. SIMULATED, NOT MEASURED.