Designing a Plasma Flux Compression Generator for Pulsed Nuclear Propulsion

Nuclear (fission, fusion, and hybrid fission/fusion) propulsion systems promise dramatic reduction in trip times for numerous interplanetary destinations. Pulsed fission, fusion, and fission/fusion hybrid systems require significant instantaneous power to initiate the nuclear reactions, usually stored and delivered by capacitor banks. For such systems, pulse recharge circuits are necessary for extracting some power from the microexplosions, leaving the remaining thermal and kinetic energy in the plasma available for generating thrust. This paper presents a study of such a circuit based on flux compression generation. Results using a 1-D plasma model suggest a system where the extracted energy for a high-gain system requires a small fraction of the initial plasma energy, leaving the remaining energy for thrust. The researchers demonstrate a low specific energy (35 J/kg) and high specific power (37.5 kg/kW(e)) with the proposed design. Based off these results using the simplified 1-D model, the complexity and cost of using a full 3-D model that includes kinetic and fluid effects may be justified to further explore this concept. At a high level, this design reduces some uncertainty over previous designs, making pulsed nuclear propulsion more feasible, enhancing, and enabling missions throughout the solar system.