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Nuclear instrumentation and measurement: a review based on the ANIMMA conferences

The paper describes the main challenges justifying research in these different areas, and summarizes the recent progress reported. It offers researchers and engineers a way to quickly and efficiently access knowledge in highly specialized areas.

6/18/2020 6:32:54 AM +00:00

A low power ADS for transmutation studies in fast systems

In this work, we report studies on a fast low power accelerator driven system model as a possible experimental facility, focusing on its capabilities in terms of measurement of relevant integral nuclear quantities.

6/18/2020 6:32:48 AM +00:00

Formalization of the kinetics for autocatalytic dissolutions. Focus on the dissolution of uranium dioxide in nitric medium

In this work, the kinetics rates have been measured by optical microscopy using a single particle approach. The advantages of this analytical technique are an easier management of species transport in solution and a precise following of the dissolution rate.

6/18/2020 6:32:41 AM +00:00

Evolution of the collective radiation dose of nuclear reactors from the 2nd through to the 3rd generation and 4th generation sodium-cooled fast reactors

This article discusses the evolution of the collective dose for several types of reactors, mainly based on publications from the NEA and the IAEA.

6/18/2020 6:32:35 AM +00:00

RadFET dose response in the CHARM mixed-field: FLUKA MC simulations

This paper focuses on Monte Carlo simulations aimed at calculating the dose response of the RadFET dosimeter, when exposed to the complex CHARM mixed-fields, at CERN. We study how the dose deposited in the gate oxide (SiO2) of the RadFET is affected by the energy threshold variation in the Monte Carlo simulations as well as the materials and sizes of scoring volumes.

6/18/2020 6:32:29 AM +00:00

Adaptive multilevel splitting for Monte Carlo particle transport

In the present paper, we propose an alternative version of the AMS algorithm, adapted for the first time to the field of particle transport.

6/18/2020 6:32:21 AM +00:00

Artificial neural network surrogate development of equivalence models for nuclear data uncertainty propagation in scenario studies

Scenario studies simulate the whole fuel cycle over a period of time, from extraction of natural resources to geological storage. Through the comparison of different reactor fleet evolutions and fuel management options, they constitute a decision-making support.

6/18/2020 6:32:15 AM +00:00

Probabilistic risk bounds for the characterization of radiological contamination

This paper presents several alternative statistical approaches which are based on much weaker hypotheses than the Gaussian one, which result from general probabilistic inequalities and order-statistic based formulas.

6/18/2020 6:32:09 AM +00:00

Structural integrity assessment and stress measurement of chasnupp-1 fuel assembly skeleton: under tensile loading condition

This study has been made in an attempt to find the structural integrity of the Chashma Nuclear power plant-1 FA skeleton at room temperature. The finite element (FE) analysis has been performed using ANSYS, in orderto determinethe elongationofthe FAskeleton as wellas the locationofmax. stress and stresses developedin axial direction under tensile load of 9800 N or 2 g being the FA handling or lifting load [Y. Zhang et al., Fuel Assembly Design Report, SNERDI, China, 1994].

6/18/2020 6:32:03 AM +00:00

Gamma ray transport simulations using SGaRD code

SGaRD (Spectroscopy, Gamma rays, Rapid, Deterministic) code is used for the fast calculation of the gamma-ray spectrum, produced by a spherical shielded source and measured by a detector. The photon source lines originate from the radioactive decay of the unstable isotopes.

6/18/2020 6:31:57 AM +00:00

Methodology for the nuclear design validation of an Alternate Emergency Management Centre (CAGE)

The methodology is devised by coupling different codes. The study of weather conditions as part of the data of the site will determine the relative concentrations of radionuclides in the air using ARCON96.

6/18/2020 6:31:51 AM +00:00

Towards spatial kinetics in a low void effect sodium fast reactor: core analysis and validation of the TFM neutronic approach

The studies presented in this paper are performed in the general framework of transient coupled calculations with accurate neutron kinetics models able to characterize spatial decoupling in the core. An innovative fission matrix interpolation model has been developed with a correlated sampling technique associated to the Transient Fission Matrix (TFM) approach.

6/18/2020 6:31:44 AM +00:00

Local correlated sampling Monte Carlo calculations in the TFM neutronics approach for spatial and point kinetics applications

These studies are performed in the general framework of transient coupled calculations with accurate neutron kinetics models. This kind of application requires a modeling of the influence on the neutronics of the macroscopic cross-section evolution.

6/18/2020 6:31:38 AM +00:00

Reassessment of gadolinium odd isotopes neutron cross sections: scientific motivations and sensitivity-uncertainty analysis on LWR fuel assembly criticality calculations

This article shows how the most recent gadolinium cross sections evaluations appear inadequate to provide accurate criticality calculations for a system with gadolinium fuel pins. In this article, a sensitivity and uncertainty analysis (S/U) has been performed to investigate the effect of gadolinium odd isotopes nuclear cross sections data on the multiplication factor of some LWR fuel assemblies.

6/18/2020 6:31:31 AM +00:00

Analysis and optimization of minor actinides transmutation blankets with regards to neutron and gamma sources

We propose here to implement an optimization methodology of the blankets design with regards to various parameters such as the local spectrum or the mass to be loaded, with the objective of minimizing the final neutron source of the spent assembly while maximizing the transmutation performances of the blankets.

6/18/2020 6:31:25 AM +00:00

Neutronics characterization of an erbia fully poisoned PWR assembly by means of the APOLLO2 code

For this purpose, a simplified thermal-hydraulic analysis was performed in order to evaluate the effects on fuel thermal conductivity of adding erbia to uranium oxide. The results obtained allow to conclude that an Er-doped assembly enriched to >5 wt.% in 235U represents an advantageous solution for very long fuel cycles, and it is so suited for very high burnups.

6/18/2020 6:31:19 AM +00:00

Visual Simultaneous Localization and Mapping (VSLAM) methods applied to indoor 3D topographical and radiological mapping in real-time

In this communication, we will present our current developments of an instrument that combines these methods and parameters for specific applications in the field of nuclear investigations.

6/18/2020 6:31:12 AM +00:00

State of the art on nuclear heating measurement methods and expected improvements in zero power research reactors

The paper focuses on the recent methodological advances suitable for nuclear heating measurements in zero power research reactors. This bibliographical work is part of an experimental approach currently in progress at CEA Cadarache, aiming at optimizing photon heating measurements in low-power research reactors.

6/18/2020 6:31:06 AM +00:00

A role of electrons in zirconium oxidation

This process periodically speeds up the corrosion of the zirconium cladding in the aqueous coolant due to the breakaway of the dense part of oxide scale when its thickness reaches 2 mkm. It is shown that the electronic resistivity of zirconia is not limiting the zirconium oxidation at working temperatures.

6/18/2020 6:31:00 AM +00:00

Economic appraisal of deployment schedules for high-level radioactive waste repositories

The deep geological repository (DGR) is considered as the definitive management solution for high-level waste (HLW). Countries defined different DGR implementation schedules, depending on their national context and political choices.

6/18/2020 6:30:54 AM +00:00

Energetic and economic cost of nuclear heat impact on the cost of desalination

In the context of this work, simplified models have been developed to describe the thermodynamics of power conversion, the energetics of multi-effect evaporation (MED), and the costs of electricity and heat cogenerated by the dual-purpose power plant.

6/18/2020 6:30:48 AM +00:00

Impact of correlations between core configurations for the evaluation of nuclear data uncertainty propagation for reactivity

In this paper, a traditional adjoint method is used to propagate ND uncertainty on reactivity and reactivity coefficients and estimate correlations between different states of the core. We show that neglecting those correlations induces a loss of information in the final uncertainty.

6/18/2020 6:30:42 AM +00:00

Dissolution of uranium dioxide in nitric acid media: what do we know?

This article draws a state of knowledge of the dissolution of uranium dioxide in nitric acid media. The chemistry of the reaction is first investigated, and two reactions appear as most suitable to describe the mechanism, leading to the formation of monoxide and dioxide nitrogen as reaction by-products, while the oxidation mechanism is shown to happen before solubilization.

6/18/2020 6:30:36 AM +00:00

Oxygen segregation in pre-hydrided Zircaloy-4 cladding during a simulated LOCA transient

This work aims at determining the key parameters controlling the average oxygen profile within the sample in the two-phase regions at 1200 °C. High temperature steam oxidation tests interrupted by water quench were performed using pre-hydrided Zircaloy-4 samples.

6/18/2020 6:30:30 AM +00:00

Lithium and boron analysis by LA-ICP-MS results from a bowed PWR rod with contact

In this work, the equipment was used to investigate the distribution of lithium (7Li) and boron (11B) in the outer oxide at the bow contact area. Depth profiling in the clad oxide at the opposite side of the rod to the point of contact, which is considered to have experienced normal operating conditions and which has a typical oxide thickness, evidenced levels of ∼10–20 ppm 7Li and a 11B content reaching hundreds of ppm in the outer parts of the oxide, largely in agreement with the expected range of Li and B clad oxide concentrations from previous studies.

6/18/2020 6:30:23 AM +00:00

Development of the MFPR model for fission gas release in irradiated UO2 under transient conditions

The fission gas release microscopic model of the mechanistic code MFPR is further developed for modelling of enhanced release from irradiated UO2 fuel under transient conditions of the power ramp tests, along with the microstructure evolution characterised by the formation of a new population of large intragranular bubbles with a rather wide size distribution (from 30 to 500 nm), observed in transient-tested UO2 fuel samples.

6/18/2020 6:30:17 AM +00:00

Positron annihilation spectroscopy study of lattice defects in non-irradiated doped and un-doped fuels

In this study, we investigated the microstructure of such doped fuels as well as a reference standard UO2 by positron annihilation spectroscopy (PAS). Although this technique is particularly sensitive to lattice point defects in materials, a wider application in the UO2 research is still missing.

6/18/2020 6:30:11 AM +00:00

Proposal of new oxidation kinetics for sponge base E110 cladding tubes material

Study of high temperature steam oxidation kinetics during the high temperature oxidation was carried out on the sponge base E110 cladding tubes material in the temperature range 600–1300 °C. The oxidation kinetics derived from the weight gain measurements showed a parabolic rate law for temperatures 1100 °C and higher only.

6/18/2020 6:30:05 AM +00:00

A simplified geometrical model for transient corium propagation in core for LWR with heavy reflector

In this document, we present a simplified geometrical model (0D model) for the in-core corium propagation transient. A degraded core with a formed corium pool is used as an initial state. This state can be obtained from a simulation computed with an integral code.

6/18/2020 6:29:59 AM +00:00

The role of power sources in the European electricity mix

In this study, we use MIXOPTIM, a Monte-Carlo simulator of the behavior of a mix of power sources on a territory, to evaluate the performance of the present EU power mix. After a validation on the French mix, we applied it to the whole EU territory and made variational calculations around the present mix to evaluate the performance impacts induced by small changes in installed renewable power and nuclear power.

6/18/2020 6:29:53 AM +00:00