A study of the requirements of p-11B fusion reactor by tokamak system code

TL;DR

This study extends a tokamak system code to analyze p-11B fusion reactors, highlighting the impact of relativistic bremsstrahlung and helium confinement on fusion performance and gain.

Contribution

It introduces the incorporation of relativistic bremsstrahlung into the tokamak system code for p-11B fusion analysis and evaluates the effects of synchrotron radiation and helium confinement.

Findings

Fusion gain exceeds 1 under certain parameters without synchrotron radiation loss.

Fusion gain decreases significantly when synchrotron radiation is considered.

Helium confinement time must be shorter than energy confinement time for optimal performance.

Abstract

Most tokamak devices including ITER exploit the D-T reaction due to its high reactivity, but the wall loading caused by the associated 14MeV neutrons will limit the further development of fusion performance at high beta. To explore p-11B fusion cycle, a tokamak system code is extended to incorporate the relativistic bremsstrahlung since the temperature of electrons is approaching the rest energy of electron. By choosing an optimum p-11B mix and ion temperature, some representative sets of parameters of p-11B tokamak reactor, whose fusion gain exceeds 1, have been found under the thermal wall loading limit and beta limit when synchrotron radiation loss is neglected. However, the fusion gain greatly decreases when the effect of synchrotron radiation loss is considered. Helium ash also plays an important role in the fusion performance, and we have found that the helium confinement time must be below the energy confinement time to keep the helium concentration ratio in an acceptable range.