Deep-Burnable Glass Micro-Fuel
Theoretical and Conceptual Substantiation of Deep-Burnable Glass Micro-Fuel for Fast Reactors
Tech Area / Field
- FIR-MAT/Materials and Materials Conversion/Fission Reactors
- FIR-FUC/Fuel Cycle/Fission Reactors
3 Approved without Funding
Kurchatov Research Center, Russia, Moscow
- Argonne National Laboratory (ANL) / West, USA, ID, Idaho Falls
Краткое описание проектаThe given project is devoted to theoretical and calculative substantiating the concept of glass micro-fuel with deep burning out of heavy atoms for reactors on fast neutrons.
In decreasing the grain size of ceramic (for example, oxide) nuclear fuel from microns up to nanometers and less, i.e. getting an amorphous fuel, it is possible to increase efficiency of retention of fission products in this ceramics and preventing its swelling. It is pointed out the results of numerous investigations with simple and complex polycrystalline materials under irradiation.
The accent is done in the mechanism of capture of fission products by micro-structural defects, first of all, radio-induced vacancies which continuously appear in ceramic fuel under action of neutrons and fission fragments, are united in units, pores, and bubbles appreciably increasing the volume of fuel.
Quintessence of the project is searching the eutectics of UO2-UC-USi, made from fine mixture of components in order to create the fuel with extremely small swelling factor and maximal "capacity" for the fission fragments. Being stably amorphous (glass), such the fuel will have high volumetric density of equilibrium microscopic defects of vacancy type, which effectively absorb solid and gaseous fission products, not changing amorphous structure of the solid matrix. Such the phase has practically unlimited "capacity" of distributed drains in the radiating defects.
1. Micro-structural and atomic dynamic simulation of the disorder structure of amorphous fuel by methods of Monte Carlo and molecular dynamics for:
· obtaining data on the behavior of fuel under irradiation,
· extracting correlation functions, spectra elementary excitations, diffusive modes, characteristic atomic configurations of disorder fuel matrix, and parameters of solubility in it of fission fragments,
· developing a model of structurally stable state of the nanometer-ceramic (amorphous) fuel in strong radiating influence.
2. Substantiation of the opportunity and the conditions for making the glass (amorphous-stable) fuel in order to increase the burn-out of heavy atoms in spectrum of fast neutrons. It assumes:
· to prove the concept for designing the glass micro-fuel on the given attributes including nuclear, structural, thermal, and physical properties,
· to obtain and analyze the data on phase diagrams of multi-component systems of uranium such as UO2-UC-USi,
· to reveal its eutectic points as the most acceptable for glassing the fuel.
3. Calculation of the optimal composition and structural configuration of the glass micro-fuel.
4. The analysis of the obtained results for correcting the subsequent calculations and numerical experiments.
As the main objectives, the project has development and verification of phase model for amorphous-stable structure in the scope for R&D substantiating the concept for designing the glass micro-fuel.
The commercially significant overall results of activities can be the designer and technological documentation for developing the technical proposals on searching the trial eutectics in the system of UO2-UC-USi.
The activity is completed by the issue of documentation covered in a report of calculation results and prepared file of input data for further usage in different stages in developing the technology for getting the glass fuel.