Conceptual Design of Steady-State Compact Fusion Neutron Sources based on GDT

Commercial application of fusion energy requires developing fusion nuclear science and technology, especially after the International Thermonuclear Experimental Reactor (ITER) program. The development of fusion nuclear science and technology needs a high flux fusion neutron source, which can simulate the neutron environment of the fusion reactor. Many kinds of neutron sources have already been designed and constructed, including radioactive isotope neutron sources, nuclear reactor neutron sources, and accelerator-based neutron sources. However, neutron sources used for development of fusion nuclear science and technology requires especially fusion neutron spectrum and high neutron flux up to 2 MW/m². Currently, plasma-type fusion neutron sources can base on normal tokamak, spherical tokamak, magnetic mirror and stellarator. Among these devices, a fusion neutron source based on Gas Dynamic Trap (GDT) magnetic mirror is featured with inherent steady state operation, compact structure, easy construction and maintenance, relatively low tritium consumption, and flexible operation. In recent years, the basic principles of GDT operation have been demonstrated, and neutron sources based on GDT have also been proposed by many institutes. The conceptual design of the GDT based fusion neutron sources in this report has laid the groundwork for its further detailed conceptual design and engineering design. The key technologies, such as high field magnet and high-power steady-stated NBI, were assessed. The potential application of this kind of fusion neutron source on development of fusion nuclear science and technology as well as driving fusion–fission hybrid systems has been preliminarily evaluated. To improve the performance and economic efficiency of GDT based fusion neutron source and reduce the technologies requirement of magnet and NBI, some innovative were also proposed and investigated. Under this research contract, in section 1, we will briefly describe the characteristic of GDT and its potential application, as well as the development roadmap of GDT based fusion neutron source in China proposed by Institute of Nuclear Energy Safety Technology (INEST), Chinese Academy of Sciences. In section 2, the conceptual design activities of GDT based fusion neutron source in INEST are presented, including design guidelines, objectives and preliminary plasma parameters of GDT based fusion neutron source. In section 3, we assess the feasibility of different application, including fusion materials testing and nuclear waste transmuting, and evaluates the key technologies needed to support those applications. In section 4, we explore some innovative concepts for improving the performance of GDT based fusion neutron source. (author)