Feasibility of a Full Cycle D-D Fusion Reactor

Full cycle deuterium-deuterium (D-D) fusion reactors benefit from the burning of D-D reaction products providing additional power via the deuterium-tritium (D-T) and deuterium-helium-3 (D-He³) fusion. However, the high temperatures needed to attain significant D-D fusion reactivity require consideration of relativistic effects and additional radiative loss mechanisms, which are insignificant in D-T reactors. Here, we present a 0-D model for the Lawson criterion of a generalized D-D reactor accounting for high energy radiative loss mechanisms. The confinement of impurity and fusion ash is considered using a set of fixed ratios of particle to energy confinement times. The supra-thermal He³ and tritium fusion products, produced at energies of a few MeV, have enhanced reactivity. This effect is included by adding on slowing down distributions for fast ions, enhancing ion burn-up by about 5 percent, which is beneficial for overall plasma performance. Finally, the 0-D model is extended to a simple 1-D model, including temperature and density profiles calculated using empirical scaling laws. This is iteratively solved to obtain steady-state conditions, allowing for the exploration of required reactor parameters.