Frontiers in Nuclear Engineering | New and Recent Articles

Development of a nuclear thermal propulsion (NTP) engine is pursued by government and industry. Current deployment regulations require that experimental efforts are heavily complemented and guided by modeling and simulation. Challenges arise when directly simulating the physics of such systems at steady-state operation and especially during transients due to strongly coupled local and global effe…

Nuclear security event response within all-hazards systems requires coordination among emergency management, regulatory, law enforcement, technical and forensic actors operating under distinct mandates. This study examines how nuclear security event response is specified within Türkiye’s national emergency management system. Based on structured documentary analysis of publicly available planning,…

Geological disposal safety assessments distinguish normal evolution from inadvertent human intrusion. Normal evolution is treated as the expected long-term behaviour of the disposal system; human intrusion is treated as a stylised future human action whose probability cannot be forecast reliably over geological timescales. This distinction is justified, but it can obscure a protection-relevant qu…

In tightly coupled multiphysics simulations, the conventional Monte Carlo assumption of piecewise-constant material properties is no longer valid, as temperature and density fields vary continuously in space. Current approaches to this problem each impose limitations on accuracy, generality, or computational efficiency. This work introduces the Lagrange Error-Adaptive Collision Sampling (LEACS) m…

Radiation measurements by citizen appeared for the first time in the aftermath of the Chornobyl accident and received a renewed interest in the aftermath of the Fukushima accident. At that time, several networks of citizen measurement of radioactivity appeared in Europe, mainly acting for education to radioactivity and the science of measurement and for education, both initial and continuous, to …

Cloud computing is increasingly being adopted in nuclear and radiological monitoring systems to address the limitations of traditional on-premises infrastructures. Radiation Detection Systems (RDS), which rely on distributed sensor networks, generate large volumes of data requiring scalable storage, real-time processing, and secure transmission. While cloud integration enhances flexibility, mobil…

This work presents the development and evolution of the test cell (TC) neutronics geometry models for IFMIF-DONES (International Fusion Materials Irradiation Facility–Demo Oriented Neutron Source), supporting detailed Monte Carlo–based nuclear analyses for design assessment and optimization. Beginning with the IFMIF/EVEDA configuration, successive model versions have been developed to reflect maj…

This paper presents Nagra’s systematic methodology for developing safety scenarios for the post-closure safety case in support of the Swiss general licence application for deep geological disposal of radioactive waste. The approach builds on the assessment basis, performance assessment outcomes, and international guidelines. It combines top-down safety-function reasoning with bottom-up FEP screen…

Gas-cooled reactors are among the most promising Generation IV nuclear energy systems, and helium-based binary mixtures are attractive candidate coolants because of their favorable thermophysical and chemical properties. In this work, a numerical investigation was conducted to study the distribution evolution and thermal stratification of a He–Ar gas mixture in a closed cylindrical vessel. The ef…

Recent advancements in nuclear energy, particularly in the development of Molten Salt Reactors (MSRs), emphasize a shift towards integrating advanced technology for enhanced safety and efficiency. MSRs utilize unique fuel cycles and offer significant advantages over traditional reactors, including flexibility in fuel utilization and improved safety mechanisms. This study introduces a multiphysics…

The susceptibility of the boiling water reactor (BWR) Limerick Unit 1 to fuel fragmentation, relocation, and dispersal during a postulated large-break loss-of-coolant accident (LBLOCA) was calculated using a multiphysics framework. The simulations include full-core, rod-resolved neutronic, thermal hydraulic, and fuel performance models using the VERA, TRACE, and BISON codes. This work focused on …

Inertial electrostatic confinement fusion devices (fusors) are becoming increasingly attractive neutron sources, and are well suited for global distribution with great humanitarian benefits. However, such neutrons are agnostic to the user’s intent, so could in theory be used for malicious means. This paper discusses the feasibility of using fusors to convert fertile thorium-232 or uranium-238 int…

The safe geological disposal of low- and intermediate-level radioactive waste relies on a passive multi-barrier system. This paper presents the provisional Swiss design for the low- and intermediate-level waste (L/ILW) emplacement caverns and their expected evolution. In the current design, containers are stacked within the L/ILW disposal caverns, and the remaining void space is backfilled with a…

Deep geological repositories for radioactive waste rely on geological barriers to isolate waste and impede or limit radionuclide migration over long geological timescales or until radioactivity has decreased to natural radiation levels. This study summarises the main geological evidence and arguments for the containment-providing rock zone (CRZ), including the host rock Opalinus Clay, as effectiv…

This paper evaluates the neutronic feasibility and multi-physics safety of a hybrid Accident Tolerant Fuel (ATF) assembly in a VVER-1000 reactor. The proposed design strategically employs standard UO2 within the inner core and a high-density U3Si2 matrix in the peripheral pins to take advantage of inter-assembly thermalization for cycle length extension. Coupled evaluations were performed using O…

Industrial gamma radiography is a widely used non-destructive testing (NDT) technique, but it involves significant radiological risks that require precise planning of shielding and safety distances. Current practices rely heavily on in-situ radiometric measurements, which are time-consuming and may increase unnecessary operator exposure during setup and verification stages. This work presents RAD…

The safe geological disposal of high-level radioactive waste requires a passive multi-barrier system. This paper describes the engineered barriers foreseen in the provisional Swiss repository concept, covering both design aspects as well as evidence for their long-term performance. Disposal canisters made of carbon steel will be used for the encapsulation of spent nuclear fuel and vitrified high-…

The post-closure biosphere assessment and modelling in support of the general licence application for a deep geological repository for radioactive waste provides the basis for evaluating radiological consequences should radionuclides released from the geological repository reach the surface and near-surface environments. The assessment approach comprises the modelling of radionuclide migration in…

This paper describes the deep geological repository concept considered by Nagra in support of its recent general licence application and the methodology used by Nagra to demonstrate its post-closure safety. The concept presented is for a deep geological repository for high-level waste (HLW) and for low- and intermediate-level waste (L/ILW) located in the Opalinus Clay host rock in Switzerland. Th…