•Ordinary Concrete (OC) and Heavy Concrete (HC) have been optimized and designed for IFMIF-DONES based on ITER reference.•Technical properties (density, compressive and flexural strength) are ...superior in comparison to ITER reference.•Neutron shielding efficiency of HC is higher – thermal neutron absorption for HC is more than 8 times higher than for OC.•Neutron shielding efficiency of optimized concrete is better than for ITER reference concrete – both in case of OC and HC.•Calculation methods of neutron shielding efficiency are effective for comparison – experimental verification ongoing.
The aim of this study was to optimize and evaluate structural and shielding concrete for the IFMIF-DONES building. An ordinary concrete of lime-dolomite aggregate from local sources has been chosen for structural concrete and magnetite aggregate was chosen for heavy-weight radiation shielding. The reference for concrete materials design was the one used in the ITER project. After investigations of raw materials, a group of prebatches were prepared and technical properties – density of compressive strength, were measured. Finally, two compositions have been elaborated – one for structural concrete of density 2.5 g/cm3 and the second for radiation shielding concrete of density 3.9 g/cm3. Then a set of 50 × 50 × 5 cm3 slabs were prepared and sent to the Nuclear Physics Institute of the CAS in the Czech Republic for shielding mock-up experiments. Also the other technical properties like E-modulus, bending strength etc. have been determined. Additionally, radiation shielding efficiency has been calculated based on atomic composition.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
IFMIF-DONES is a facility under construction in Granada, whose main goal is the validation and characterization of materials under a fusion prototypic irradiation field. This field is created by the ...interaction of a high energy intense continuous deuteron beam and a flowing liquid lithium target. The requirements imposed on the beam at the interaction point are a complex trade-off among the scientific experimental needs for the materials irradiation defined at the top-level requirements (20 dpa in a volume of 0.3 dm3 and 50 dpa in 0.1 dm3), and the technical constraints of several systems such as the Accelerator Systems, the Lithium Systems, and the Test Systems. Recent simulations with the initial definition of beam-on-target requirements showed the necessity of redefining them in order to fulfill the irradiation needs. This contribution will address the main challenges to gather the inputs for the definition and reassessment of the beam-on-target requirements. A comparison detailing the main changes compared to the previous ones will be given, together with a short overview of the studies ongoing by different systems to analyze the impact of each beam-on-target requirements on the performance of the whole facility.
•Fusion materials irradiation.•Deuteron accelerator.•High current accelerator.•Beam delivery system.•Beam on-target.
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The international fusion materials irradiation facility-DEMO-oriented neutron source (IFMIF-DONES) is a facility that is designed under the framework of the EU fusion roadmap. It is going to be an ...essential irradiation facility for testing and qualifying candidate materials under severe irradiation conditions of a neutron field having an energy spectrum like the one present in a fusion power reactor. The material specimens are irradiated in a containment structure named the test cell (TC), which is part of the test systems (TS). The TC also houses a part of the other major system (lithium system, LS), which provides the liquid lithium for the reaction through a piping system. At a point, the lithium piping needs to exit the TS, but the primary safety boundary must be continuous around these penetrations. Therefore, a special barrier, called the test systems–lithium systems interface cell (TLIC), has been developed around the piping system to provide a safety-approved and remotely maintainable vacuum boundary envelope. In this paper, the integrated design development of the TLIC is described, consisting of the design development according to the RCC-MRx code, the remote-handling (RH) needs, and the procedures and safety-related special needs of the design.
Alignment strategy for IFMIF-DONES facility Arranz, Fernando; Becerril, Santiago; Bernardi, Davide ...
Fusion engineering and design,
March 2024, 2024-03-00, Volume:
200
Journal Article
Peer reviewed
Open access
This article addresses the challenges associated with the alignment of the equipment within the IFMIF DONES installation and presents the strategy devised to achieve acceptable levels of uncertainty. ...The primary obstacles stem from the need to align equipment located in different rooms, some of which are inaccessible for manual operations. Additionally, the elevated radiation levels in certain areas impose restrictions on the fiducials that can be employed.
The article details the outcomes of implementing the proposed alignment procedure, including the specific equipment used and the achieved levels of uncertainty.
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We present an optimized algorithm for assigning fibres to targets in next-generation fibre-fed multi-object spectrographs. The method, which we have called the draining algorithm, ensures that the ...maximum number of targets in a given target field is observed in the first few tiles. Using randomly distributed targets and mock galaxy catalogues, we have estimated that the gain provided by the draining algorithm, compared to a random assignment, can be as much as 2 per cent for the first tiles. For a survey such as the Baryon Oscillation Spectroscopic Survey (BigBOSS), this would imply saving for observation several hundred thousand objects or, alternatively, reducing the covered area in ∼350 deg2. An important advantage of this method is that the fibre collision problem can be solved easily and in an optimal way. We also discuss the additional optimizations of the fibre-positioning process. In particular, we show that if we allow for the rotation of the focal plane, we can improve the efficiency of the process by ∼3.5-4.5 per cent, even if only small adjustments are permitted (up to 2°). For instruments that allow large rotations of the focal plane, the expected gain increases to ∼5-6 per cent. Therefore, these results strongly support the use of focal plane rotation in future spectrographs, as far as the efficiency of the fibre-positioning process is concerned. Finally, we discuss the implications of our optimizations and provide some basic hints for an optimal survey strategy, based on the number of targets per positioner.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
We present an optimized algorithm for assigning fibers to targets in next-generation fiber-fed multi-object spectrographs. The method, that we named draining algorithm, ensures that the maximum ...number of targets in a given target field is observed in the first few tiles. Using randomly distributed targets and mock galaxy catalogs we have estimated that the gain provided by the draining algorithm as compared to a random assignment can be as much as 2% for the first tiles. This would imply for a survey like BigBOSS saving for observation several hundred thousand objects or, alternatively, reducing the covered area in ~350 sq. deg. An important advantage of this method is that the fiber collision problem can be solved easily and in an optimal way. We also discuss additional optimizations of the fiber positioning process. In particular, we show that allowing for rotation of the focal plane can improve the efficiency of the process in ~3.5-4.5% even if only small adjustments are permitted (up to 2 deg). For instruments that allow large rotations of the focal plane the expected gain increases to ~5-6%. These results, therefore, strongly support focal plane rotation in future spectrographs, as far as the efficiency of the fiber positioning process is concerned. Finally, we discuss on the implications of our optimizations and provide some basic hints for an optimal survey strategy based on the number of targets per positioner.
Fiber-fed spectrographs dedicated to observing massive portions of the sky are increasingly being more demanded within the astronomical community. For all the fiber-fed instruments, the primordial ...and common problem is the positioning of the fiber ends, which must match the position of the objects of a target field on the sky. Amongst the different approaches found in the state of the art, actuator arrays are one of the best. Indeed, an actuator array is able to position all the fiber heads simultaneously, thus making the reconfiguration time extremely short and the instrument efficiency high. The SIDE group (see http://side.iaa.es) at the Instituto de Astrofísica de Andalucía, together with the industrial company AVS and the University of Barcelona, has been developing an actuator suitable for a large and scalable array. A real-scale prototype has been built and tested in order to validate its innovative design concept, as well as to verify the fulfillment of the mechanical requirements. The present article describes both the concept design and the test procedures and conditions. The main results are shown and a full justification of the validity of the proposed concept is provided.
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