Anticipated transients without scram in an innovative power nuclear reactor of anomalously high power

Abstract

The article considers the possibility of creating a safe power reactor of anomalously high power. This may be relevant in the transition to large-scale safe and environmentally acceptable nuclear power. The safety justification is carried out based on mathematical modeling of the most dangerous emergency modes from among ATWS (anticipated transients without scram). With the use of a number of innovations (the UN-PuN-U cermets fuel used, a coolant based on lead with a high concentration of the 208Pb isotope, and tungsten fuel cladding), it was possible to ensure the safety of a fast reactor with an electric power of up to 3 GW. In contrast to previously proposed innovations, the article considers core layouts containing fuel pins with claddings made entirely of tungsten. Emergency modes are modeled approximately based on solving three groups of equations: a system of point kinetic equations, a non-stationary heat conduction equation, which, and a reactivity balance equation. The value of the void reactivity effect is estimated based on the solution of the gas-kinetic neutron transport equation. Reserves have been identified in further increasing the power and safety of the power reactor. They are associated with the optimization of the size of granules of ceramic and metal powders in the fuel composition.