Hybrid “Fusion-Fission” Reactor Facility on Thorium Fuel with a Source of Additional Thermonuclear Neutrons

The results of full-scale numerical experiments of a hybrid thorium-containing fuel cell facility operating in a close-to-critical state due to a controlled source of fusion neutrons are discussed in this work. The facility under study was a complex consisting of two blocks. The first block was based on the concept of a high-temperature gas-cooled thorium reactor core. The second block was an axially symmetrical extended plasma generator of additional neutrons that was placed in the near-axial zone of the facility blanket. The calculated models of the blanket and the plasma generator of D-T neutrons created within the work allowed for research of the neutronic parameters of the facility in stationary and pulse-periodic operation modes. This research will make it possible to construct a safe facility and investigate the properties of thorium fuel, which can be continuously used in the epithermal spectrum of the considered hybrid fusion-fission reactor.

Enhancement of irradiation resistance and experimental research of compact electronics for ITER Radial X-ray Camera

International Thermonuclear Experimental Reactor (ITER) Radial X-ray Camera (RXC) is installed in the equatorial port #12 (middle drawer) to measure the poloidal profile of the plasma x-ray emission with high spatial and temporal resolution. According to the irradiation test results with Co-60 gamma ray source, Cf-252 neutron source and the result in Deuterium - Tritium (DT) accelerator neutron irradiation experiment for RXC electronics before, the weak parts of the circuit have been improved by radiation resistance design such as using radiation-hard power chip and optimizing the Field Programmable Gate Array (FPGA) code. Other factors related to radiation, such as easiness of maintenance, compact electronics structure and remote state monitoring are also considered in the design. The performance of the electronics and chassis has been preliminarily verified in Experimental Advanced Superconducting Tokamak (EAST) experiments showing resistance to interference from discharge environment. Besides, the irradiation resistance of electronics was investigated in high fluence neutron irradiation experiment in fission reactor, where the detector, pre-amplifier, mid-amplifier and cables under test received the accumulated neutron fluence over 9.89×1013n/cm-2 (1MeV equivalent), and the quality of output signal was monitored in real time. It’s found after the experiment that the pre-amplifier worked well, while the detector and mid-amplifier were partly damaged.

Theoretically and under very special applied conditions a nuclear fission reactor may explode as nuclear bomb

This article/presentation describes a theoretical and applied research in nuclear fission reactor systems. It concerns with theoretical approaches and in very special applied cases consideration where a common nuclear fission reactor system may be considered to explode as nuclear bomb. This research gives critical impacts to the design, operation, management and philosophy of nuclear fission reactors systems. It also includes a sensitivity analysis of a particular applied problem concerning the core melting of a nuclear reactor and its deposit to the bottom of reactor vessel. Specifically, in a typical nuclear fission power reactor system of about 1000 MWe, the nuclear core material (corium) in certain cases can be melted and it may deposited in the bottom of nuclear reactor vessel. So, the nuclear criticality conditions are evaluated for a particular example case(s). Assuming an example composition of melted corium of 98 tones of U238 , 1 tone of U235 , 1 tone Pu239 and 25 tones Fe56 (supporting material) in a 5 m diameter of a finite cylindrical nuclear reactor vessel it is found that it may result in nuclear criticality above the unit. This condition corresponds to Supercritical Fast Nuclear Fission Reactor case, which may under certain very special applied conditions to nuclear explode as nuclear bomb.

Designing a compact, portable and high efficiency reactor

In this paper, in order to produce high-energy neutrons, the design of a compact, portable and high efficiency reactor based on a plasma focus device is investigated. The COMSOL Multiphysics software was used to investigate and optimize 16 plasma focus devices with different stored energies for producing neutrons. To keep the fission reactor at the subcritical condition, fuel assembly containing a specific combination of fission fuel of [Formula: see text]U – [Formula: see text]Pu was used. As a result of energetic neutrons produced in the plasma focus device, no radioactive waste remained in the reactor. In addition, an efficient gas cooling system that absorbed and transferred heat was designed using the COMSOL Multiphysics software. The absorbed heat was transferred to the thermo-photo-voltaic converter, and thus electricity was generated with an efficiency of about 40%. Electrical and thermal energies are calculated in each shot for every plasma focus device. Finally, we showed that high frequency plasma focus devices had a high potential to produce energy.