Nuclear Safety for Advanced Neutron Sources
Theoretical and Experimental Substantiation of Nuclear Safety for Advanced Pulsed Neutron Sources
Tech Area / Field
- FIR-NSS/Nuclear Safety and Safeguarding/Fission Reactors
- FIR-EXP/Experiments/Fission Reactors
- FIR-NOT/Nuclear and Other Technical Data/Fission Reactors
- FIR-OTH/Other/Fission Reactors
8 Project completed
Senior Project Manager
Svetlova A V
Joint Institute of Nuclear Research, Russia, Moscow reg., Dubna
- VNIIEF, Russia, N. Novgorod reg., Sarov
- Argonne National Laboratory (ANL) / Intense Pulsed Neutron Source Division, США, IL, Argonne\nForschungszentrum Jülich / European Spallation Source Project (ESS), Germany, Jülich\nForskningscenter Riso Afdelinen for Materialers Fysik og Kemi, Denmark, Roskilde\nKyoto University / Research Reactor Institute, Japan, Osaka
Project summaryThis project aims to carry out both theoretical and experimental research directed towards substantiation and improvement of nuclear safety at advanced periodic operation, pulsed neutron sources (PNS). This task is currently the focus because recent scientific and technical interest has been focused on employing PNS in different fields of science and techniques. Along with unique operating setups based on pulsed nuclear reactors (IBR-2), powerful proton accelerators with nonmultiplying targets (IPNS, LANCE etc.), and subcritical systems with electron accelerators (IBR-30), there are a number of projects being planned in Japan, Europe, Korea, China, and Russia for the development and construction of PNS designed to obtain intense pulsed neutron fluxes for scientific purposes, as well as to use neutrons for the “transmutation” (burn-up) of long-lived fission products.
The problem of providing for the safe and reliable operation of the PNS in service today and to those under design is complicated and varied and, clearly, the solution depends on the type of PNS. There are, however, some problems that are common to all PNS, and the solution of these would provide for the highly safe operation of these setups. The common major problem is to provide for supervision and control over the chain reaction (i.e., over Keff) under routine and emergency conditions.
The proposed project comprises elaboration of some of the crucial problems that are key to the evaluation and improvement of PNS nuclear safety for operations and design.
The principal goals of the project are as follows:
1. Development of technique for monitoring the Кeff value in every power pulse and for monitoring stochastic (random) Кeff fluctuations of subcritical systems with a proton or electron accelerator. Theoretical, methodical, and experimental works using the IBR-30 pulsed booster are planned.
2. Development and improvement of the dynamic models for booster and reactor pulsed systems, and the creation of software packages to simulate the transition processes during various emergency situations. Here it is suggested that the IBR-2 reactor and the IBR-30 booster be used for the experiments to check the model calculations. In addition, general-purpose software packages for monitoring PNS dynamics, applicable for installation at a wide range of advanced PNS, are to be developed.
3. Development of computer codes for simulating the time-dependent characteristics of subcritical fast assemblies using the Monte Carlo method (e.g., the MCNP-code). Experiments measuring pulse shape will be carried out with the subcritical IBR-30 assembly for different Кeff for the purpose of creating a database for the matching of calculation results and the comparison of the applied computer codes.
4. Calculation of Кeff variation in subcritical fast assemblies in accordance with energy generation. Separation of the components of the Кeff variation determined by the change in fuel isotope composition. Comparison of calculated and experimental data for fast reactors with small active zones.
5. Evaluation of the effect of principal factors on the safety level of fast reactors with small active zones and negative reactivity.
6. Simulation and evaluation of the possibility of applying the stage system as PNS with the purpose of improving safety, reliability, and cost-effectiveness.
The principal advantage of this project is the possibility of its rapid completion due to the long operating experience gained from the IBR-2, IBR-30 and creation experience of intensive resonance neutron source IREN (IREN – Russian abbreviation) at the Frank Laboratory of Neutron Physics of JINR, and also the possibility of applying the experience of other organisations, i.e., development engineers and manufacturers of subcritical assemblies and active zones. Another advantage is the availability of equipment for measurements with the above mentioned facilities.
The proposed project gives a possibility to scientists and engineers previously involved with development and manufacture of weapons to apply their knowledge and experience to long-term non-military activities in the field of nuclear technologies.
The experience gained during fulfilment of the project will be used in the operation, design, and construction of intense PNS.