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In this article authors discuss a design of static shading that has its aim to fulfill several important requirements in order to provide a building’s envelope design optimization. The demonstrated shading system design meets all the necessary requirements for comfort conditions in the space, that include efficiency of shading for mitigation of harmful (excessive) solar gains (that may lead to space overheating and increase in cooling loads) and acceptable amount of useful light entering the space. To design such static shading authors followed several crucial steps that are discussed in detail. The steps are further summarized in a design workflow. The shading is validated to ensure comfortable thermal conditions and visual comfort inside the space under investigation by the use of specific software. The importance of introduction of digital twin technology to the passive energy-efficient design of buildings by means of passive control of thermal and visual conditions with the use of shading systems is as well discussed.

The basic facility of the Factory of Superheavy Elements (SHE), the DC-280 cyclotron, in the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research has been completed. Both new and experimentally tested engineering solutions of the laboratory underlie the project. Planned beam intensities of up to 10 pμA of ions with average masses (A ~ 50) are one order of magnitude higher than those produced at the U-400 cyclotron up to now. From 2016 to 2018, the DC-280 cyclotron equipment was installation and set up. The first 84Kr14+ ion beam was accelerated in the DC-280 on December 26, 2018, and extracted to the accelerated ion transportation channel on January 17, 2019. In March 2019, beams of accelerated 84Kr+14 ions with an intensity of 1.36 pμA and 12С+2 ions with an intensity of 10 pμA were extracted from the DC-280 to the beam transportation channel with an energy of about 5.8 MeV/nucleon. The main task of the new accelerator is to implement a long-term research program at the SHE Factory aimed at the synthesis of new elements (Z ≥ 119) and a detailed study of nuclear–physical and chemical properties of previously discovered elements nos. 112–118.

The status of the project of the DC-280 cyclotron is presented. The DC-280 will be the basic facility of the Super Heavy Element Factory which is being created at the FLNR JINR. The energy of the ions extracted from the cyclotron will be vary from 4 up to 8 MeV/amu. The expected ion beam intensity at DC-280 extraction is 10 pμA for ions with masses of 50–60. The main parts of the DC-280 are already made and are being assembled. In according to FLNR plans the cyclotron has to be assembled in the period from 2016 to 2017. The cyclotron commissioning will be in 2018.

International audience; The safety of gas transportation pipelines under fatigue loading remains an important issue. The purpose of the present study is to better evaluate the fatigue crack growth (FCG) behavior by carrying out analysis/predictions and experiments in full-size pipeline steels. A full characterization was made using several samples of an X42 grade pipeline steel, to characterize the monotonic and the fatigue behavior. Fatigue tests on full-scale pipeline steels under pressure loading were performed. The potential drop (PD) method applied to pressurized pipes makes it possible to monitor and quantify both crack initiation and crack propagation. These tests served as a basis for numerical comparison. Crack propagation of the full-size pipeline steel was simulated by finit element analysis (FEA) using an adaptive re-meshing approach implemented as part of the Z-set/Zebulon software. Simulation allows predicting fatigue crack growth life on pipes using results of tests on specimens as an input.

The design of the high-voltage axial injection system for the DC-280 cyclotron that is being constructed at the Flerov Laboratory of Nuclear Reactions (FLNR) at the Joint Institute for Nuclear Research (JINR) is presented. The injection system will make it possible to efficiently inject ions of elements ranging from helium to uranium with the ratios of their atomic mass to the charge varying from 4 to 7.5.

The DC-110 heavy ion cyclotron for industrial production of track membranes has been developed and created at the Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research. The cyclotron is equipped with an electron cyclotron resonance ion source operating at a frequency of 18 GHz. The accelerator complex was put into operation in 2012 and 40Ar6+, 86Kr13+, and 132Xe20+ ion beams with a energy of 2.5 MeV/nucleon and intensity of 13, 14.5, and 10.5 μA, respectively, were produced. Irradiation of a polymer film was carried out on a specialized channel and track membranes with a high uniformity of pores were obtained. The DC-110 accelerator complex can produce up to 2 million square meters of track membranes per year.

International audience; Models classically used to describe the probability of brittle fracture in nuclear power plants are written on a macroscale. Physical phenomena are not naturally captured by this type of approach, so that the application of the models far from their identification domain (temperature history, loading path) may become questionable. To improve the quality of the prediction of resistance and life time, microstructural information, describing the heterogeneous character of the material and its deformation mechanisms has to be taken into consideration. The purpose of the paper is to propose a model able to describe local stress and strain fields in 16MND5 bainitic steel. These data will then be used as critical variables for multiscale failure models. The microstructure of 16MND5 steel is made of bainitic packets coming from former austenitic grains, which are not randomly oriented. Knowing the macroscopic stress is thus not sufficient to describe the stress-strain state in ferrite. An accurate model must take into account the actual microstructure, in order to provide realistic local stress and strain fields. After providing some observations and the analysis of the bainitic microstructure, the paper shows a quantitative model of the morphology and the crystallography, then a finite element analysis involving crystal plasticity.

GALS is the experimental setup intended for production and research of isobaric and isotopically pure heavy neutron-rich nuclei. The beam line consists of two parts. The initial part is used for transport of the primary 136Xe ion beam with the energy of 4.5-9.0 MeV/amu from the FLNR cyclotron U-400M to the Pb target for production of the studying ion beams. These beams have the following design parameters: the charge Z = +1, the mass A = 180-270 and the kinetic energy W = 40 keV. The second part placed after the target consists of the SPIG (QPIG) system, the accelerating gap, the electrostatic Einzel lens, 90-degree spectrometric magnet (calculated value of the mass-resolution is equal to 1400) and the beam line for the transportation of the ions from the magnet focal plane to a particle detector. The results of simulation of the particle dynamics and the basic parameters of all elements of the beam line are presented.

A project of the high-resolution magnetic analyzer MAVR is proposed. The analyzer will comprise new magnetic optical and detecting systems for separation and identification of reaction products in a wide range of masses (5-150) and charges (1-60). The magnetic optical system consists of the MSP-144 magnet and a doublet of quadrupole lenses. This will allow the solid angle of the spectrometer to be increased by an order of magnitude up to 30 msr. The magnetic analyzer will have a high momentum resolution (10-4) and high focal-plane dispersion (1.9 m). It will allow products of nuclear reactions at energies up to 30 MeV/nucleon to be detected with the charge resolution ~1/60. Implementation of the project is divided into two stages: conversion of the magnetic analyzer proper and construction of the nuclear reaction products identification system. The MULTI detecting system is being developed for the MAVR magnetic analyzer to allow detection of nuclear reaction products and their identification by charge Q, atomic number Z, and mass A with a high absolute accuracy. The identification will be performed by measuring the energy loss (ΔE), time of flight (TOF), and total kinetic energy (TKE) of reaction products. The particle trajectories in the analyzer will also be determined using the drift chamber developed jointly with GANIL. The MAVR analyzer will operate in both primary beams of heavy ions and beams of radioactive nuclei produced by the U400 - U400M acceleration complex. It will also be used for measuring energy spectra of nuclear reaction products and as an energy monochromator.

International audience; The problem of determining the probability of failure in a brittle material from a micromechanical local approach has recently been addressed in few works ([1], [2] and [3]), all related to bainite polycrystals at different temperatures and states of irradiation. They have separately paved the ground for a full-field modelling with high realism in terms of constitutive modelling and microstructural morphology. This work first contributes to enhance this realism by assembling the most pertinent/valuable characteristics (dislocation density based model, large deformation framework, fully controlled triaxiality conditions, explicit microstructure representation of grains and sub-grains, ... ) and by accounting for a statistically representative Volume Element; this condition indeed must be fulfilled in order to capture rare events like brittle micro-fractures which, in the stress analysis, correspond to the tails of distribution curves. The second original contribution of this work concerns the methodology for determining fracture probabilities: rather than classically - and abruptably - considering a polycrystal as broken as soon as an elementary link (grain or sub-grain) has failed, the possibility of microcrack arrest at microstructural barriers is introduced, which enables to determine the probability of polycrystal failure according to different scenarii of multiple micro-fractures.

International audience; Models classically used to describe the probability of brittle fracture in nuclear power plants are written on the macroscopic scale. Its is not easy to surely capture the physical phenomena in such a type of approach, so that the application of the models far from their identification domain (temperature history, loading path) may become questionable. To improve the quality of the prediction of resistance and life time, microstructural information, describing the heterogeneous character of the material and its deformation mechanisms has to be taken into consideration. This paper is devoted to 16MND5 bainitic steel. Bainitic packets grow in former austenitic grains, and are not randomly oriented. Knowing the macroscopic stress is thus not sufficient to describe the stress-strain state in ferrite. An accurate model must take into account the actual microstructure, in order to provide realistic local stress and strain fields, to be used as inputs of a new class of cleavage models based on the local behavior. The paper shows the first two steps of the study: mesh generation and finite element computations using crystal plasticity.