Search

The ITER Neutral Beam Test Facility, in an advanced construction in Padova, includes the installation, tests, and optimization of the full prototype of the ITER Heating Neutral Beams injectors (HNBs), named MITICA. The MITICA Neutral Beam Injector will host its main items in a SS304L vacuum vessel composed of two modules, connected between them on site: the Beam Source Vessel (cubic of 5 m side and 67 tons weight) containing the ion Beam Source and the Beam Line Vessel (section 4.5 m x 4.5 m, length 11 m and 76 tons weight) containing the Beam Line Components and the Cryopumps. The project requirements were transferred in the manufacturing design and in the fabrication process of these large vessels produced through welding and machining. The following steps were in particular carried out before and during manufacturing: o FE analyses to assess the structural integrity and limited deformations under vacuum loading conditions (leading to ribs reinforcement) o materials selection suitable for the specific application o qualification of special processes (welding and NDE) to ensure control of welding distortions and leak tight joints o implementation of double barrier sealings for the most critical connections o control of deformations under vacuum loads comparing displacement measurements with results of FE analyses. The Factory Acceptance Tests of the individual vessels are presented, including their Helium Leak Tests. The two vessels have been assembled on-site inside the MITICA bio-shield. They have been connected through a double sealing barrier composed of elastomer and a leak tight welded flange connection, previously qualified at the factory. The main outcomes of on-site final assembly and Site Acceptance Tests are described. Both vessels have been manufactured, installed and tested by De Pretto Industrie; the design and the technical support were provided by Consorzio RFX, while the procurement was managed by F4E.

The SPIDER Beam Source (BS), the first prototype of a full scale ion source for the ITER Heating Neutral Beam injector, was delivered to the Neutral Beam Test Facility (NBTF) site in Padova (Italy) after about five years procurement phase. A huge effort was devoted during the procurement for quality controls and testing at the supplier’s workshops. Several activities were also carried out on NBTF site for verification/adjustment of interfaces, solution of still open issues, as well as final tests before and after installation inside the vacuum vessel. The NBTF Team undertook the BS site acceptance tests including: pressure and leak tests of the hydraulic circuits; electrical tests; measurement of magnetic field profiles; functionality tests of diagnostics installed on the BS; checks of grids alignment by means of laser tracker. Accurate positioning of the BS inside the vacuum vessel was performed and various service lines were connected in a tight space. Several improvements were undertaken in order to guarantee reliability and reduce the risks during the commissioning and experimental campaign in 2018. After installation, the integrated commissioning phase was initiated, powering the RF and high voltage circuits, followed by the first operation in vacuum.

The full-size ITER ion source prototype SPIDER (Source for the Production of Ions of Deuterium Extracted from a Radio frequency plasma) has recently started beam operation, whose objective is to produce 100 keV, 60 A hydrogen negative ions for 1 h. The source is presently operated in the volume regime, and the beam power is consequently limited. In such a configuration, the high resolution calorimeter STRIKE (Short-Time Retractable Instrumented Kalorimeter Experiment), even though uncooled, may be used instead of the SPIDER beam dump without limiting the beam-on time. STRIKE is formed by unidirectional carbon fiber-carbon matrix (CFC) composite tiles that are exposed to the beam while their temperature is recorded by using two infra-red cameras. This setup, thanks to the moderate broadening of the temperature profile guaranteed by the anisotropy of CFC, allows for the determination of detailed features of the beam current distribution (spatial resolution is about 2 mm). Furthermore, positively biasing the CFC tiles permits a direct electrical measurement of the negative ion beam current. Besides the total beam current and beam uniformity, which can be retrieved both by calorimetry and electrical measurement, beamlet divergence and deflection can be determined by infra-red thermography. This contribution describes the characterization of the SPIDER negative ion beam as a function of the source and accelerator parameters by means of the diagnostic calorimeter STRIKE in the volume regime.

For ITER operations, additional heating systems are required. One of these systems is the neutral beam injector (NBI). The SPIDER experiment, a small-scale NBI, is going to be built with the aim to optimize the beam source. For this reason it is provided with several diagnostics, among which the Short-Time Retractable Instrumented Kalorimeter Experiment (STRIKE). In this contribution, a characterization of the Carbon Fiber Composite (CFC) tiles, which are the main component of the diagnostic, is presented. Such analyses include tests with a power laser, exposure to particle beams and thermal stress tests. The results are discussed, which will drive the definition of the acceptance tests of the final supply of CFC tiles.

This paper describes the final design of the Short-Time Retractable Instrumented Kalorimeter Experiment (STRIKE) for the SPIDER experiment (Source for Production of Ions of Deuterium Extracted from Radio frequency plasma) under construction at the Consorzio RFX premises. The STRIKE diagnostic will be used to characterise the SPIDER beam during short pulse operation (several seconds) to verify the degree of attainment of ITER requirements about the maximum allowed beam non-uniformity. After a preliminary design developed in the last few years, the complete STRIKE diagnostic system has been recently subjected to a final review and is now ready for construction. The main components of the system are: an array of 16 tiles made of Carbon Fibre Composite, which will be exposed to the high power density beam (of the order of 20 MW/m22) exiting from the SPIDER Beam Source; a supporting and positioning system, based on a set of structures made of stainless steel, with controlled moving systems, to be installed within the SPIDER vacuum vessel; a set of thermal, electric and thermo-graphic sensors to properly detect the operating conditions. The paper will focus in particular on the development of the engineering design of the supporting and positioning system, with a description of the relevant CAD and FEM analyses, and will give an overview of the complete system, with reference to the manufacture of CFC tile prototypes and to the choice of the complete set of sensors.

The ion source NIO1 (Negative Ion Optimization 1) was developed and installed as a reduced-size model of multi-aperture sources used in neutral beam injectors. NIO1 beam optics is optimized for a 130 mA H- current (subdivided in 9 beamlets) at a Vs=60 kV extraction voltage, with an electron-to-ion current ratio Rj up to 2. In an initial phase, NIO1 was operated with Vs=0 to verify the coupling of radiofrequency (rf) power Pf to plasma. The distinction between capacitively coupled plasma (E-mode, consistent with a low electron density plasma ne) and inductively coupled plasma (H-mode, requiring larger ne) was clearly related to several experimental signatures, especially for air or nitrogen plasmas, where E to H transition was observed with Pf about 0.5 kW (with hysteresis). In hydrogen, the same transition may require about 1 kW, so that air cooling of the rf window was improved. Beams of H- and O- were separately extracted (using pure gases as input); since no caesium is yet introduced into the source, the expected ion currents are typically lower than 10 mA; this requires a lower acceleration voltage Vs (to keep the same perveance). Operation at lower voltages and current (as appropriate in this phase) is possible, but use of weaker deflection magnets in the extraction grid (EG) or use of heavier gases (oxygen) is then advisable. Preliminary experiments indicate the need of increasing the ampere-turns in magnetic filter and the bias voltage to reduce Rj (still very large, about 150 for oxygen), in qualitative agreement with theoretical and numerical models. In a separate test stand, NIO1 caesium oven was tested, with deposition on a molybdenum substrate, and advanced Cs dispensers are in development.

Additional heating will be provided to the thermonuclear fusion experiment ITER by injection of neutral beams from accelerated negative ions. In the SPIDER test facility, under construction at Consorzio REX in Padova (Italy), the production of negative ions will be studied and optimised. To this purpose the STRIKE (Short-Time Retractable Instrumented Kalorimeter Experiment) diagnostic will be used to characterise the SPIDER beam during short operation (several seconds) and to verify if the beam meets the ITER requirement regarding the maximum allowed beam non-uniformity (below ±10%). The most important measurements performed by STRIKE are beam uniformity, beamlet divergence and stripping losses. The major components of STRIKE are 16 1D-CFC (Carbon matrix-Carbon Fibre reinforced Composite) tiles, observed at the rear side by a thermal camera. The requirements of the ID CFC material include a large thermal conductivity along the tile thickness (at least 10 times larger than in the other directions); low specific heat and density; uniform parameters over the tile surface; capability to withstand localised heat loads resulting in steep temperature gradients. So ID CFC is a very anisotropic and delicate material, not commercially available, and prototypes are being specifically realised. This contribution gives an overview of the tests performed on the CFC prototype tiles, aimed at verifying their thermal behaviour. The spatial uniformity of the parameters and the ratio between the thermal conductivities are assessed by means of a power laser at Consorzio RFX. Dedicated linear and non-linear simulations are carried out to interpret the experiments and to estimate the thermal conductivities; these simulations are described and a comparison of the experimental data with the simulation results is presented.

O melão (Cucumis melo L.) é uma fruta muito apreciada por suas qualidades e sua produção vem crescendo e ganhando espaço no mercado nacional e internacional. Em regiões como o Noroeste do Rio Grande do Sul, destaca-se como uma nova alternativa de renda para vários agricultores. Neste contexto, o presente trabalho teve como objetivo analisar o potencial fitoquímico de alguns cultivares de melão da região Noroeste do Rio Grande do Sul. A análise fitoquímica utilizando como farmacógeno as folhas, foi realizada para a verificação da presença de metabólitos secundários, tais como: saponinas, cumarinas, cardiotônicos, cianogenéticos, alcalóides, taninos, antraquinonas, flavonoides, e óleos voláteis. Também foi avaliado o teor de suco a partir dos frutos. Dentre os cinco cultivares analisados, Gaúcho, Imperial, Hy Mark, Magelan, e Cantaloupe, o cultivar Gaucho apresentou a maior variedade em metabólitos secundários. Na avaliação do teor de suco a cultivar Magelan se destacou em comparação às demais cultivares testadas. The melon (Cucumis melo L.) is a fruit highly appreciated for its qualities and its production has been growing and gaining space in the national and in the international market. In regions like the northwest of Rio Grande do Sul - Brazil, it stands out as a new income alternative for farmers. In this context, this study aimed to analyze the phytochemical potential of some melon cultivars in the northwest region of Rio Grande do Sul. The phytochemical analysis, using the leaves as pharmacogen, was performed to verify the presence of secondary metabolites such as saponins, coumarins, cardiac glycosides, cyanogenetic glicosides, alkaloids, tannins, anthraquinones, flavonoids and volatile oils. The juice content from the fruits was also evaluated. Among the five analyzed cultivars, Gaucho, Imperial, Hy Mark, Magelan and Cantaloupe, cultivar Gaucho had the greatest variety of secondary metabolites. In the assessment of the juice content, cultivar Magelan was superior compared to the remaining tested cultivars.

This paper presents the results of numerical simulations and experimental tests carried out to assess the feasibility and suitability of graphite castellated tiles as beam-facing component in the diagnostic calorimeter of the negative ion source SPIDER (Source for Production of Ions of Deuterium Extracted from Radio frequency plasma). The results indicate that this concept could be a reliable, although less performing, alternative for the present design based on carbon fiber composite tiles, as it provides thermal measurements on the required spatial scale.

Neutral Beam Injectors (NBI) based on negative ion conversion are fundamental to increase the plasma temperature in magnetic confinement fusion devices.. In the framework of the accompanying activities in support to the ITER NBI test facility a relatively compact radiofrequency (RF) ion source, named NIO1 (Negative Ion Optimization phase 1) is being developed and tested in Padua, Italy, in collaboration between Consorzio RFX and INFN. This contribution reports the recent status of the experiment, including the operation in air and oxygen and the first beam measurements. Future improvements to enhance the negative ion current and reduce the amount co-extracted electrons are also discussed.

To study and optimize negative ion production and acceleration, in view of the use of neutral beam injectors in the ITER project, the SPIDER test facility (particle energy 100keV; beam current 50A, distributed over 1280 beamlets) is under construction in Padova, with the aim of testing beam characteristics and to verify the source proper operation, by means of several diagnostic systems. An array of tungsten wires, directly exposed to the beam and consequently heated to high temperature, is used in similar experiments at IPP-Garching to study the beam optics, which is one of the most important issues, in a qualitative way. The present contribution gives a description of an experimental investigation of the behavior of tungsten wires under high heat loads in vacuum. Samples of tungsten wires are heated by electrical currents and the emitted light is measured by a camera in the 400-1100nm wavelength range, which is proposed as a calibration tool. Simultaneously, the voltage applied to the wire is measured to study the dependency of emissivity on temperature. The feasibility study of a wire calorimeter for SPIDER is finally proposed; to this purpose, the expected behaviour of tungsten with the two-dimensional beam profile in SPIDER is numerically addressed.

In the framework of the accompanying activity for the development of the two neutral beam injectors for the ITER fusion experiment, an instrumented beam calorimeter is being designed at Consorzio RFX, to be used in the SPIDER test facility (particle energy 100keV; beam current 50A), with the aim of testing beam characteristics and to verify the source proper operation. The main components of the instrumented calorimeter are one-directional carbon-fibre-carbon composite tiles. Some prototype tiles have been used as a small-scale version of the entire calorimeter in the test stand of the neutral beam injectors of the LHD experiment, with the aim of characterising the beam features in various operating conditions. The extraction system of the NIFS test stand source was modified, by applying a mask to the first gridded electrode, in order to isolate only a subset of the beamlets, arranged in two 3x5 matrices, resembling the beamlet groups of the ITER beam sources. The present contribution gives a description of the design of the diagnostic system, including the numerical simulations of the expected thermal pattern. Moreover the dedicated thermocouple measurement system is presented. The beamlet monitor was successfully used for a full experimental campaign, during which the main parameters of the source, mainly the arc power and the grid voltages, were varied. This contribution describes the methods of fitting and data analysis applied to the infrared images of the camera to recover the beamlet optics characteristics, in order to quantify the response of the system to different operational conditions. Some results concerning the beamlet features are presented as a function of the source parameters.

The ITER project requires additional heating provided by two injectors of neutral beams resulting from the neutralisation of accelerated negative ions. To study and optimise negative ion production, the SPIDER test facility (particle energy 100keV; beam current 50A) is under construction in Padova, with the aim of testing beam characteristics and to verify the source proper operation. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon fibre carbon composite tiles. Some prototype tiles have been employed in 2012 as a small-scale version (mini-STRIKE) of the entire system to investigate the features of the beam from BATMAN at IPP-Garching. As the BATMAN beamlets are superposed at the measurement position, about 1m from the grounded grid, an actively cooled copper mask is located in front of the tiles; holes in the mask create an artificial beamlet structure. Recently the mini-STRIKE has been updated, taking into account the results obtained in the first campaign. In particular the spatial resolution of the system has been improved by increasing the number of the copper mask holes. Moreover a custom measurement system has been realized for the thermocouple signals and employed in BATMAN in view of its use in SPIDER. The present contribution gives a description of the new design of the system as well as of the thermocouple measurements system and its field test. A new series of measurements has been carried out in BATMAN. The BATMAN beam characterisation in different experimental conditions is presented.

The ITER neutral beam injection system is being designed to provide 33 MW of heating from two injectors, with an upgrade to 50 MW possible with a third injector; such heating power will be provided by accelerating negative ions to high energies, 1 MeV, and neutralizing them. These neutrals are then injected into the tokamak where they impart their energy by collisions. To study and optimize negative ion production, the SPIDER prototype is under construction in Padova, Italy, whose beam has an energy of 100 keV and a current of 48 A. The instrumented calorimeter Short-Time Retractable Instrumented Kalorimeter Experiment (STRIKE) has been designed with the main purpose of characterizing the SPIDER negative ion beam in terms of beam uniformity and beam divergence during short operations (several seconds). STRIKE is made of 16 1-D carbon fiber composite (CFC) tiles, intercepting the whole beam and observed from the rear side by infrared (IR) cameras. With two identical samples of the CFC material and the IR camera under assessment, a reduced version of the entire calorimeter has been built, with the purpose of characterizing its diagnostic properties. This mini-STRIKE was used in the BATMAN experiment at Max Planck Institut fu?r Plasmaphysik (Garching, Germany). As the beamlet divergence in BATMAN is large, the beamlets overlap each other in the measurement position; therefore, the mini-STRIKE for BATMAN includes a copper mask, facing the beam and featuring eight apertures. Thus, eight different portions of the beam can be simultaneously sampled, with minimal overlapping of the power coming from adjacent apertures. The copper mask was actively cooled, and calorimetry was carried out. The temperature in the center of the mask and some positions along the CFC tiles was also measured. In this paper, the design of the system is presented. The calorimetry system is presented in detail as well as the procedure adopted for calorimetrical data analysis. The results of - alorimetry are presented together with preliminary correlations with the BATMAN beam features.

The ITER project requires additional heating via injection of neutral beams, provided by two injectors accelerating negative ions. To study and optimise negative ion production, the SPIDER prototype is under construction in Padova, whose beam has an energy of 100keV and a current of 50A. The instrumented calorimeter STRIKE (Short-Time Retractable Instrumented Kalorimeter Experiment) has been developed with the main purpose of characterising the SPIDER negative ion beam in terms of beam uniformity and beam divergence during short pulse operations (several seconds). STRIKE is made of 16 1D Carbon Fibre Composite (CFC) tiles, intercepting the whole beam and observed on the rear side by infrared (IR) cameras. Prototypes of the CFC material were procured and this contribution presents experimental tests and numerical simulations devoted to the characterisation of the CFC properties and to the assessment of the performance of the diagnostic. Tests are described, performed using a CO 2 laser to investigate the spatial resolution of the diagnostic on the scale lengths and with the experimental layout expected in SPIDER. Data recorded by an IR camera during the experiments are compared with simulations aiming to reproducing the experimental data with the purpose of validating the thermal parameters of CFC.

The ITER project requires neutral beam injection; such additional heating power will be provided by two injectors accelerating negative ions. To study and optimise negative ion production, the SPIDER prototype is under construction in Padova, Italy, whose beam has an energy of 100 keV and a current of 50 A. The instrumented calorimeter STRIKE (Short-Time Retractable Instrumented Kalorimeter Experiment) has been designed with the main purpose of characterising the SPIDER negative ion beam in terms of beam uniformity and beam divergence during short operations (several seconds). STRIKE is made of 16 1D Carbon Fibre Composite (CFC) tiles, intercepting the whole beam and observed on the rear side by infrared (IR) cameras. With two identical samples of the CFC material and with the IR camera under assessment, a reduced version of the entire calorimeter has been built, with the purpose of characterising its diagnostic properties. This mini-STRIKE was used in the BATMAN experiment at IPP (Garching, Germany). As the beamlet divergence in BATMAN is large, the beamlets are superposed in the position where the diagnostic is located; consequently the mini-STRIKE for BATMAN includes a copper mask, facing the beam and featuring 8 apertures. Thus, eight different portions of the beam can be simultaneously sampled, with minimal overlapping of the power coming from adjacent apertures. The copper mask was actively cooled and calorimetry was carried out. The temperature in the centre of the mask and in some positions along the CFC tiles was also measured. In this contribution the design of the system is presented, along with the tests performed before the installation of mini-STRIKE in BATMAN. The calorimetry system is presented in detail as well as the procedure adopted for calorimetrical data analysis. Results of calorimetry are presented together with preliminary correlations with the BATMAN beam features.

To characterise the beam of SPIDER, a diagnostic calorimeter (dubbed STRIKE) is being developed. Its main components are one-directional carbon fibre carbon composite tiles (CFC) and thermal cameras. A small-scale system composed of two tile prototypes and one thermal camera (mini-STRIKE) is used at IPP-Garching with the aim of investigating the properties of the BATMAN beam. The presentation will describe design, installation and commissioning of the mini-STRIKE in BATMAN. The first results of the characterisation of the BATMAN beam by the mini-STRIKE in various operating conditions will be presented.

This study describes the physico-chemical properties and the skin permeation profile of quercetin (Q) and 3-O-methylquercetin (MQ) from lipid nanoemulsions. Formulations composed of octyldodecanol, egg lecithin, water (NE) and cetyl trimethyl ammonium bromide (CNE) were obtained by spontaneous emulsification. This procedure yielded monodisperse nanoemulsions exhibiting a mean droplet size of approximately 200-300 nm. Nanoemulsions were further characterized in terms of zeta-potential, surface tension, and morphology by transmission electron microscopy. The amount of flavonoids incorporated into nanoemulsions reached nearly 100% (at 1 mg/mL). The permeation studies were carried out using ear pig skin mounted in Franz diffusion cells. The overall results have shown a slow permeation profile of both Q and MQ from nanoemulsions. However, a higher permeation flux rate of flavonoids from CNE (approximately 0.2 microg/cm2/h) as compared to NE (approximately 0.08 microg/cm2/h) was observed, showing the effect of the positively charged surface of CNE on this parameter. Such results open interesting perspectives for the topical administration of the flavonoids Q and MQ.

To study and optimise negative ion production for the ITER neutral beam injectors, a test facility is under construction in Padova with the aim of testing beam characteristics and to verify the source proper operation. The instrumented calorimeter STRIKE (short-time retractable instrumented kalorimeter experiment) is being developed to characterise the SPIDER (Source for Production of Ion of Deuterium Extracted from RF plasma) beam during short operations. The paper presents an investigation of the response of STRIKE measurement systems. It results that biasing is necessary to cope with the influence of secondary electrons on current measurements; moreover, despite the discretisation of the recorded thermal patterns introduced by the pixels of thermal cameras, a sufficient spatial resolution is expected.

In the development of the neutral beam injector for ITER experiment, the test facility SPIDER is going to be built. To measure the beam parameters, several diagnostics are used. One of them is the Short-Time Retractable Instrumented Kalorimeter Experiment (STRIKE) which measures beam uniformity, beamlet divergence, and stripping losses. This contribution gives an overview of the diagnostics dedicated to these measurements: thermal cameras, thermocouples, current sensors, and electrostatic sensors. The specifications of these diagnostics have been defined according to the results of electrostatic and thermal simulations. A failure modes and effects analysis has been performed during the design. Consequently the project of the STRIKE diagnostics has been optimized to reduce the possible failure risks.

Cesium evaporation, aimed at enhancing the production of negative ions, has recently started during the last experimental campaigns in Source for the Production of Ions of Deuterium Extracted from a Radio frequency plasma (SPIDER). In view of the full-scale ITER heating neutral beam injector (HNBI) future operations, Megavolt ITER Injector and Concept Advancement (MITICA), understanding the behavior of cesium during plasma operation is necessary to optimize the generation of negative hydrogen ions. Determining the contribution of the different mechanisms affecting the cesium distribution in the source requires a characterization of the desorption energies of the cesium compounds deposited over the source walls. The temperature programed desorption (TPD) diagnostic allows to estimate these energies using a pair of tungsten filaments, and can also be used as a Langmuir-Taylor detector. Two identical versions of the diagnostic have been assembled, giving the possibility to perform tests and characterizations on one of the copies, while having the second copy installed and operational in SPIDER. This work presents the design and development of the device, as well as experimental results in a testing vacuum chamber and in SPIDER. Finally, first estimations of the desorption energies of cesium compounds are carried out to support the plasma-Cs models for SPIDER.