The European Journal of Physics N (EPJ-N)
Not a member yet
448 research outputs found
Sort by
Development of TopMC 1.0 for nuclear technology applications
No full textParticle transport plays an important role in nuclear technology applications. As a generalized methodology, Monte Carlo is widely employed for particle transport. We investigated several key difficulties in the field, specifically addressing aspects like voxel modeling, coupled photon-electron transportation, and advanced pulse height tallying methodologies. We have developed some essential technologies to enhance the capabilities of the Multi-functional Program for Neutronics Calculation, Nuclear Design and Safety Evaluation (TopMC). This contribution presents the progress in TopMC’s R&D, including the voxel model establishment based on medical image data and fast particle tracking method, an electron transport mechanism grounded in the condensed history approach, and a variance reduction strategy to improve the efficiency of pulse height tallies. Moreover, a series of applications in the nuclear technology field were used to validate and verify TopMC, demonstrating its accuracy and efficiency. TopMC can be applied in particle transport of Boron Neutron Capture Therapy (BNCT), nuclear logging, gamma radiation detection systems, electron accelerator, etc
Status of Serpent Monte Carlo code in 2024
No full textThe Serpent Monte Carlo code has been in public distribution for 15 years, and has a large international user basis with both research and commercial applications. Serpent is currently developed as part of the Kraken multi-physics framework, which has dedicated capabilities for core-level reactor physics analyses. In Kraken, Serpent can be used either as a high-fidelity neutronics solver, or for generating homogenized group constants for the Ants nodal neutronics code. The neutron and photon transport modes in Serpent enable using the code also for various stand-alone applications beyond reactor physics, such as radiation shielding and fusion neutronics. This paper presents a review of the current status and capabilities of Serpent, corresponding to the latest release 2.2.1. The main features are introduced, with references to publications with more detailed methodological descriptions
Sustainable nuclear education and training in Europe and beyond – Examples of the ENEN2plus, TOURR and GRE@T-PIONEeR projects
No full textMaintaining education at an advanced level open at European universities has been a major challenge during the past 10–15 years. The aftermaths of the Fukushima accident and phasing out of nuclear power in some countries resulted in a decreasing student enrolment at universities in nuclear science and engineering. Although providing courses at the BSc and MSc level remained possible in some cases, offering more advanced and specialized courses was made difficult, due to too few students such courses typically attract at a given university. In response to the alarming situation, different initiatives at the European levels were undertaken. These initiatives were designed to foster collaboration among various European universities with the purpose of complementing each other’s expertise, course offering, and access to facilities. Also, more flexible ways of providing education were implemented, so that the offered courses could attract enough students. This was made possible thanks to the use of online educational techniques, allowing to share students and teachers between courses. Finally, actions were undertaken to make nuclear science and engineering more visible and attractive. In this paper, examples from the ENEN2plus, TOURR and GRE@T-PIONEeR projects are reported
MODENA project: decay heat prediction using non-destructive assay
No full textThe long-term safety of nuclear waste disposal is a major challenge for countries with nuclear energy programs. Across Europe, (deep) geological repositories have been identified as the best solution for the permanent isolation of spent nuclear fuel (SNF) and high-level radioactive waste. These repositories use multi-barrier systems, including both engineered and geological barriers, to ensure that radioactive materials are isolated from the biosphere for thousands of years. A critical factor for the safety of geological repositories is managing the decay heat, which is the thermal energy produced by radioactive decay in SNFs. Although heat generation decreases over time, significant amounts are emitted for many years after the SNF is removed from a reactor. Improper management of decay heat can compromise the integrity of the repository barriers. Calorimetric measurements can directly measure the decay heat, but they are time-consuming and resource-intensive. To address this, the MODENA project is focused on developing a fast method to estimate decay heat that relies on measurements that will be performed on every SNF before its encapsulation to verify calculated fuel properties to fulfil international safeguards regulations. These measurements are non-destructive gamma and neutron measurements. The model uses only key radionuclides such as Cs-137 and Eu-154, along with neutron emissions, which allows the prediction of decay heat without the need for additional measurements. The strength of the methodology developed in the MODENA project is its flexibility. The model is based on measurement data from radionuclides that are expected to be measurable at encapsulation and can be adapted to well-known measurement instruments, which makes it easy to apply this model in different countries. Improving decay heat prediction could lead to a more efficient use of available resources, ultimately ensuring optimized sustainability of the repository
(
No full textThis work presents different methodologies to estimate trends on α+9Be neutron production cross sections to enhance neutron spectrum calculation of alpha beryllium sources. The simulation of an Am-Be source and its comparison with several experimental references are presented. This study highlights the contribution of neutron angular distributions to reduce the gap between experimental and calculated spectra. The use of EXFOR angular distributions shows interesting results for outgoing neutrons between 5 MeV and 10 MeV. Cross sections are re-estimated using a Markov Chain Monte Carlo algorithm. The global methodology is based on a coupling between a Geant4 tool, SaG4n, and a Metropolis-Hastings algorithm. The cross sections adjustments suggest the mis-estimation of the (α, α + n) reaction and partial (α, ni) reactions. In this context, two ways of modeling cross sections are compared: one using Bayesian inference, and one using Gaussian processes
Neutronics and thermal hydraulics analysis on a Lead-bismuth-cooled fast reactor
No full textBreeding Lead-base Economical Safe System-Demonstration BLESS-D is a lead-bismuth-cooled fast reactor proposed by China State Power Investment Corporation Research Institute. It features a pool-type configuration of pressure vessel with a thermal/electric power of 300/100 MW. Neutronics and thermal hydraulics analyses are performed, mainly including a sensitivity study of the fuel components, fuel enrichment, and control-assembly arrangement on the lifetime, and the temperature field for the fuel assembly with the largest thermal power. The results show that compared with pressurized water reactor, the 239Pu production for BLESS-D is significantly higher, and the quantity of MAs is reduced, while the productions of LLFPs are at the same scale. It has also been found that under steady state conditions, the largest temperatures of the fuel pellet, cladding and coolant are all below relevant criteria, showing a good performance in the thermal hydraulics for the design. Optimizing the fuel-loading scheme for achieving a safer performance would be a part of the future’s work
Predisposal Radioactive Waste Management (PREDIS) Project Final Achievements and Impacts Overview
No full textThe PREDIS project on Predisposal of Radioactive Waste has succeeded in developing and implementing new methods, processes and technologies for treatment of challenging low-level waste (LLW) and intermediate level waste (ILW) streams. Over the 4-year duration, this Euratom project of 47 partners from 17 Member States has worked in close collaboration with 25 End User industrial members to advance the technologies associated with predisposal issues. This has included characterisation followed by treatment, conditioning and processing of metallics, liquid organic and solid organic wastes as well as with digitalization technologies for assessing performance of concrete waste packages and pre-disposal storage. Long-term modelling and performance testing have been done to verify the safety and effectiveness of the new or enhanced solutions. Value Assessments were done for some of the new solutions to ensure implementors would have sufficient tools for making choices about the potential implementation. This included life-cycle assessment of quantitative sustainability indicators and life cycle-costing for economic indicators. This project addressed new guidance on Waste Acceptance Criteria and contributed with a revised Strategic Research Agenda to guide future predisposal activities, complimentary to the holistic waste management programme. Knowledge Management actions were also an integral part of the whole project to foster competence development and capturing knowledge. Actions included training, mobility, and guidance especially through online forums such as webinars and digital training. This paper provides a snapshot of some of the key outcomes and impacts from the project, from technical as well as strategic and knowledge perspectives
Reactor performance, system reliability: instrumentation and control
No full textThe safe operation of nuclear power plants relies on Non-destructive Evaluation (NDE) of safety critical components in both the initial manufacturing phase and over the reactor’s lifecycle. The conventional approach consists of in-service inspections scheduled at regular intervals, with a periodicity adapted to expected or observed failure mechanisms and their kinetics. The three projects discussed in this paper address and challenge this approach in different ways. iWeld focuses on the inspection of welds and aims to take information about the microstructure of the material under inspection into account to improve the performance of ultrasound inspections. El-Peacetolero designed a hand-held, low power embedded optoelectronic system for an in-situ real-time assessment of aging polymers. FIND aims to develop in-situ instrumentation adapted to the specific requirements of the nuclear power industry and introduces continuous monitoring of metallic pipes to prevent their failure and optimise maintenance. The three projects discussed are at different stages: El-Peacetolero ends in February 2025, FIND just kicked off, and iWeld is halfway in between. In this review, we try to give a high-level introduction, and discuss particular challenges and achievements
Safety assessment for internal and external events on nuclear power plants and on mitigation strategies
No full textThis paper describes the main objectives and outcomes of two funded European projects (R2CA & BESEP), which have been recently finalized. They were dedicated to the safety analyses of design basis accidents and design extension conditions scenarios, covering a broad spectrum of accidents and analysis methodologies.
The R2CA project covering deterministic safety analyses set out to reduce some of the conservatisms and decoupling factors currently used for design basis accidents in safety studies or licensing calculations and to optimize emergency operating/accident management procedures. To this end, simulation tools and their coupling in calculation chains were enhanced to provide a better quantification of safety margins and a better evaluation of the radiological consequences of accident scenarios.
The BESEP project aims to develop best practices for the verification of stringent safety requirements against external hazards. The aim is achieved using an efficient and integrated set of safety engineering practices and probabilistic safety assessment. The efficient and integrated set of safety engineering practices supports the safety margins determination and safety requirement verification helping the licensing process of nuclear power plant new builds and upgrades
Qualification of advanced LEU fuels for high-power research reactor conversion designs
No full textThe two running EURATOM-funded projects EU-QUALIFY and EU-CONVERSION, coordinated by the HERACLES consortium, are developing and further qualifying advanced LEU fuel systems for conversion purposes of high-power research reactors (HPRRs). Three fuel systems have been identified as potential candidates to replace the use of highly-enriched uranium fuel, namely the uranium silicide dispersion fuel (U3Si2/Al), the U-10Mo monolithic fuel and the dispersed U-7Mo/Al fuel system. The U-Mo monolithic and the U3Si2/Al dispersion fuel systems are currently being advanced in technology readiness level, towards more representative generic test assemblies, mimicking more closely target reactor specific conditions. A number of irradiation experiments have so far been conducted on the two dispersion fuel systems and the first monolithic irradiation experiment at the Belgian BR2 reactor is targeted to commence during 2025. The post-irradiation examinations of the historical and ongoing tests will be concluded within the projects and the complementary HERACLES work programme. These projects are also important contributors in establishing industrial-level fabrication processes of high-loaded and high-density uranium silicide fuels as well as U-Mo monolithic fuels. The operational times of the current HPRRs are foreseen to be extended by their conversions and, thus, have an essential impact on the future European supply of reactor-produced medical radioisotopes