Self-Fueling Fusion Hybrid Reactor For Space Power and Propulsion

摘要

A f usion hy brid r eactor w hose fusion c omponent is the G asdynamic M irror ( GDM) i s presented as a potential energy source for utilization in space exploration. Such a reactor will consist of a fusion c omponent w hose primary function i s to s upply ne utrons t o a surrounding bl anket c ontaining fertile material where they will breed fissile material and simultaneously burn it to produce power. Since the primary function of the fusion component is to supply high energy neutrons, it can operate at or near "breakeven" condition, a much less stringent condition than that required for a pure fusion power reactor. Since the GDM is a linear, cylindrically symmetric plasma confinement device that can operate in steady state, w e find it particularly s uitable for utilization as the fusion component of the proposed hybrid reactor. Moreover, a large aspect ratio GDM is desirable from the standpoint of MHD stability and that in turn a Hows u s t o t reat t he sy stem as se mi-infinite, a nd t o e mploy t wo, one -dimensional equations t o assess the power producing capability of the system: one that describes the time evolution of the density of uranium-233 that is being bred and burned in a thorium-232 blanket, and another that describes the transport of the 14.1 MeV neutrons generated by DT reactions in the GDM and radially impinging on the thorium blanket. We find that for a reasonable design, such a reactor can produce several gigawatts of power p er cm "safely" s ince i t w ill o perate as a " subcritical" sy stem. Wh en u tilized for propulsion applications we find that it can generate a specific impulse of about 17,000 seconds at a thrust of about 29 meganewtons: a propulsion capability that can readily open the solar system to human exploration.