Overview of recent TJ-II stellarator results

The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presentedThis work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 under Grant Agreement No. 633053. It has been partially funded by the Ministerio de Ciencia, Inovación y Universidades of Spain under projects ENE2013-48109-P, ENE2015-70142-P and FIS2017-88892-P. It has also received funds from the Spanish Government via mobility grant PRX17/00425. The authors thankfully acknowledge the computer resources at MareNostrum and the technical support provided by the Barcelona S.C. It has been supported as well by The Science and Technology Center in Ukraine (STCU), Project P-507F

RESCUhE Project: Cultural Heritage vulnerability in a changing and directional climate

[EN] RESCUhE Project (Improving structural RESilience of Cultural HEritage to directional extreme hydro-meteorological events in the context of the Climate Change) is a coordinated IGME-UAM research project funded by Spanish Government (MCIN/AEI/10.13039/501100011033). The framework of this research is the predicted increase in climate change vulnerability of heritage sites and the current disconnection between both environmental research on material decay and the practical aspects of designing preventive conservation measurements.RESCUhE Project (Improving structural RESilience of Cultural HEritage to directional extreme hydro-meteorological events in the context of the Climate Change) is a coordinated IGME-UAM research project funded by Spanish Government (MCIN/AEI/10.13039/501100011033).Peer reviewe

Development of the thermal insulation devices for the JT-60SA tokamak

This report focuses on the development of the thermal insulation devices including thermal shield (TS) and cryostat for the superconducting tokamak JT-60SA.1. Design, manufacturing and acceptance test were successfully completed by 2019 and installation will be done by March 2020.2. The technique and knowledge to realize high accuracy manufacturing and short time installation of these devices will contribute to the ITER construction and DEMO design.28th IAEAFusion Energy Conferenc

Developing a large-scale dataset of flood fatalities for territories in the Euro-Mediterranean region, FFEM-DB

This data paper describes the multinational Database of Flood Fatalities from the Euro-Mediterranean region FFEM-DB that hosts data of 2,875 flood fatalities from 12 territories (nine of which represent entire countries) in Europe and the broader Mediterranean region from 1980 to 2020. The FFEM-DB database provides data on fatalities' profiles, location, and contributing circumstances, allowing researchers and flood risk managers to explore demographic, behavioral, and situational factors, as well as environmental features of flood-related mortality. The standardized data collection and classification methodology enable comparison between regions beyond administrative boundaries. The FFEM-DB is expandable, regularly updated, publicly available, and with anonymized data. The key advantages of the FFEM-DB compared to existing datasets containing flood fatalities are its high level of detail, data accuracy, record completeness, and the large sample size from an extended area

Assembly technologies of the Vacuum Vessel on JT-60SA with high accuracy

The JT-60SA superconducting tokamak is being constructed under dual projects, the EU-JA international collaboration framework and Japanese national programme. To suppress magnetic field error to less than 0.01%with respect to the toroidal magnetic field for good confinement of plasma, QST has developed a precise onsite assembly technology of tokamak components such as vacuum vessel (VV) and toroidal magnetic field coils (TFC) with size of over 10-m scale. Prior to an onsite assembly, the assembly process is carefully simulated in a three dimension CAD model, through which the location and number of the reference points for the assembly are evaluated to determine each component position. In the onsite assembly, the tokamak components are positioned by measuring with the laser tracker of a 0.5 mm spatial resolution and assembled by adjusting with shims and splice plates. The onsite assembly of the VV 340° sector has been succeeded in an allowable accuracy of +8/−4 mm with the 10 m diameter by welding sectors, each of which was circumferentially segmented and manufactured by taking into account the deformation due to the welding. The remaining 20° sector will be installed after the TF coils installation. The metrology developed for the onsite assembly of the JT-60SA is expected to be applicable to ITER whose size is the double of JT-60SA

Overview of recent TJ-II stellarator results

The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presented.ISSN:0029-5515ISSN:1741-432