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A maintainable test cell (TC) concept, which targets replacing TC key components in case of damages, for the IFMIF-DONES (International Fusion Materials Irradiation Facility – Demo Oriented NEutron Source) facility is proposed to facilitate the maintenance of key containment and biological shielding components, i.e. the liner and the surrounding concrete walls. Unlike the current TC reference design which features permanent liner and concrete shielding walls, the new proposal decouples the components which suffer relative high failure possibilities from the ones which can stay as permanent construction structures. The former ones, that are expected to be replaced in case of damage, include removable sections of the liner and part of the biological shielding materials. Fundamental mechanical solution of this configuration is briefly described, and technical feasibilities are preliminarily analyzed for the aspects of independent liner enclosure structure, maintenance scenarios using remote handling systems, etc. [ABSTRACT FROM AUTHOR]

Abstract The IFMIF-DONES (International Fusion Materials Irradiation Facility-Demo Oriented NEutron Source) test cell (TC) biological shielding is responsible of providing sufficient protection for the surrounding rooms and cells from intensive neutron irradiation and gamma radiation from inside of the TC. The TC biological shielding is composed of surrounding shielding walls, two top shielding plugs, six piping and cabling plugs (PCPs), TC floor, and removable shielding materials below the TC floor. Based on the previous TC configuration, the design of the lower shielding plug has been further developed by defining the specifications of embedded helium active cooling systems with the support of neutronic simulations, CFD analysis, and remote handling requirements. The PCP design is updated to provide sufficient space for pipe and cable connections. A preliminary piping of the water cooling system inside the heavy concrete shielding walls has been performed to qualify the capability of removing volumetric nuclear heating during irradiation experiments. The geometry of TC surrounding shielding walls are adjusted according to the latest design of PCPs and LSP as well as the requirements of the active cooling pipes which are embedded in the TC surrounding walls. [ABSTRACT FROM AUTHOR]

The test cell (TC) in IFMIF-DONES (International Fusion Material Irradiation Facility – Demo Oriented NEutron Source) is the meeting area of the three major systems (test systems, lithium systems, and accelerator systems) to host the irradiation test module, lithium target assembly and the end section of the accelerator line. Although the design of the TC, to a large extent, inherits that of the reference IFMIF-EVEDA (Engineering Validation and Engineering Design Activities) TC, design justifications are required to solve the existing major open issues such as cavitation of the lithium flow, activation and maintainability of key components, and etc. In this paper, these major open issues of the reference TC layout are addressed and a TC reconfiguration proposal, featuring arranging the lithium quench tank inside the TC, is introduced. The two concepts are investigated, analyzed, and compared on the aspects of lithium flow stability, tritium generation rate, key component maintenance scenarios, irradiation shielding, and in-TC components arrangement. [ABSTRACT FROM AUTHOR]

The Neutron Activation System (NAS) for the EU Helium Cooled Lithium Lead (HCLL) and Helium Cooled Pebble Bed (HCPB) Test Blanket Systems (TBSs) is an instrument that is proposed to determine the absolute neutron fluence and absolute neutron flux with information on the neutron spectrum in selected positions of the corresponding Test Blanket Modules (TBMs). In the NAS activation probes are exposed to the ITER neutron flux for periods ranging from several tens of seconds up to a full plasma pulse length, and the induced gamma activities are subsequently measured. The NAS is composed of a pneumatic transfer system and a counting station. The pneumatic transfer system includes irradiation ends in TBMs, transfer pipes, return gas pipes, a transfer station with a distributor (carousel), and a pressurized gas driving system, while the counting station consists of gamma ray detectors, signal processing electronic devices, and data analyzing software for neutron source strength evaluation. In this paper, a brief description on the proposed TBM NAS as well as the key components is presented, and the integration challenges of TBM NAS are outlined. [ABSTRACT FROM AUTHOR]

The test facility (TF) is one of the three major facilities of the International Fusion Material Irradiation Facility (IFMIF). Engineering designs of TF main systems and key components have been initiated and developed in the IFMIF EVEDA (Engineering Validation and Engineering Design Activities) phase since 2007. The related work covers the designs of a test cell which is the meeting point of the TF and accelerator facility and lithium facility, a series of test modules for experiments under different irradiation conditions, an access cell to accommodate remote handling systems, four test module handling cells for test module processing and assembling, and test facility ancillary systems for engineering support on energy, media, and control infrastructure. This paper summarizes the principle functions, brief specifications, and the current design status of the above mentioned IFMIF TF systems and key components. [ABSTRACT FROM AUTHOR]

Abstract: The IFMIF (International Fusion Material Irradiation Facility) test cell design has been further developed and optimized based on the existing modular test cell concept. Key features of the current test cell include actively cooled surrounding shielding walls with coverage of internal surfaces with stainless steel liner, independent two layer top shielding plugs for protecting the access cell from neutron and gamma radiation from the test cell, optimized piping and cabling plugs for accommodating pipe and cable penetrations and for minimizing neutron streaming, rearranged lithium quench tank to outside of the test cell, etc. According to preliminary neutronic calculation results, limited access to the quench tank area for maintenance after beam shut-off can be expected with the current arrangement. Maintenance of the lithium inlet and outlet pipes as well as the two beam ducts are also possible by introducing removable shielding plugs which can be removed and replaced in case of failure. [Copyright &y& Elsevier]

Abstract: The current design status of the test module interface heads (TMIHs) in the target and test cell (TTC) of the international fusion material irradiation facility (IFMIF) is described with the emphasis on new progresses in the design of cable/pipe connections and one irradiation shielding plate. A summary of the pipes and cables that will penetrate the TMIHs is outlined. In order to increase the convenience of the remote handling (RH) tools and to reduce time consumption of RH operations, piping optimization in the TMIHs is performed and industrial solutions on quick multi-pipe coupling systems for the cables and pipes are investigated. The number of pipe connections to be handled by RH tools is reduced by approximately 40%, comparing to the number of pipes that are connected to the test modules. A market available multi-pin plug/connector system is proposed to house electric power and signal lines, while a preliminary concept on multi-pipe coupling system is also introduced. In addition, a shielding plate made of lead is proposed to be installed between the pipe/cable connections and primary radiation sources to extend life spans of electric insulation materials. [Copyright &y& Elsevier]

Abstract: The reference design of the IFMIF target and test cell (TTC) which is summarized in the comprehensive design report (CDR) is reviewed and evaluated. Improved TTC conceptual designs, as well as a revision of the reference design, have been proposed in order to qualify precise and flexible positioning of test modules against the backplate in the TTC. As the result of evaluations on the existing design concepts, a referential table which addresses the design requirements and guidelines has been released and is outlined in this paper. Based on the referential table and the existing design concepts a modular TTC concept is introduced, developed, and improved aimed on providing variable in-cell operation environments, flexible accessibility for remote handling, and accurate and reliable positioning for the test modules. The current status of the preliminary engineering design based on the modular TTC concept is represented. [ABSTRACT FROM AUTHOR]

IFMIF-DONES (International Fusion Material Irradiation Facility- DEMO Oriented NEutron Source) is an accelerator based irradiation facility which is aimed to provide the irradiation data needed for the construction of DEMO. The Test Cell (TC) is the central room of IFMIF-DONES enclosing the target and the test module. This work presents the neutronics analyses conducted to provide the relevant nuclear responses for the bio-shield of the TC, including heating, radiation damage and helium production. The results for the TC steel liners covering the inner TC surface have been obtained with an unstructured mesh based interpolation approach. The results show that the softening of the neutron spectrum at the thin layer of the inner wall increases the nuclear heating as well as the helium production in SS316 L. The helium production might be of major concern if re-welding of the liner is required during the lifetime. The impact of a reduced beam footprint size on the TC nuclear responses has been analyzed and found to be insignificant comparing with the normal footprint. [ABSTRACT FROM AUTHOR]

The quench tank (QT) location in the test cell is an open issue for IFMIF-DONES (International Fusion Material Irradiation Facility- DEMO Oriented NEutron Source) design. Neutronics assessments have been carried out on two QT location options. A parametric study of the neutron streaming in the lithium chute shows a quasi-linear dependence of the neutron flux on the void thickness. For both options, activation calculations at key locations of the QT system indicate that the contact dose rate is higher than the hands-on dose limit over the whole maintenance period. In addition, the shutdown dose rates in the lithium facility room after 1-day shutdown exceed the hands-on dose limit in different levels. Therefore, remote handling is required for the maintenances of the QT in both considered locations. [ABSTRACT FROM AUTHOR]

The IFMIF Test Cell (TC) design was developed and optimized in the EVEDA phase, and finally the reference TC design was proposed. The present study is devoted to further investigations of open issues on the reference TC design. In order to examine the neutron streaming effect caused by pipe penetrations and gaps around removable shielding plugs, a new geometry model for neutronic analyses has been prepared directly from engineering CAD data by utilizing the McCad conversion software. All removable shielding plugs are separately described in the model and a detailed description of pipes was incorporated into the model. The calculation result suggests that the streaming effect is mitigated if the pipe penetration is designed appropriately, while the gaps around the shielding plugs above the TC have large impact on the radiation dose in the access cell. The concept of the reference TC design has been basically validated from the neutronics point of view, although the streaming effect should be compensated by the shielding capability of the test cell cover plate so that occupational workers can access to the access cell during operation. [ABSTRACT FROM AUTHOR]

The International Fusion Materials Irradiation Facility (IFMIF) is designated to generate a materials irradiation database for the future fusion reactors. The Test Cell (TC) accommodates the Test Modules and the lithium target assembly. Due to the nuclear heat generation, all the Test Modules inside the TC will be actively cooled. Other components like supporting structures, pipelines, cables etc., will be passively cooled by natural convection. The heat will be removed from the steel liners surrounding the TC by active water cooling. This paper concerns the thermo-hydraulic simulations of the Test Cell using Ansys-CFX. The current simulation model includes the natural convection inside the TC, several forced convective water flows in the pipelines attached on the steel liners and the helium-cooled HFTM (High Flux Test Module). The simulations provide the only means for validating the design before the construction and operation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nuclear responses in IFMIF HFTM are reevaluated based on the EVEDA phase design. [•] Latest nuclear data and the EVEDA beam footprint are utilized. [•] Averaged DPA rate of 26dpa/y can be achieved in HFTM with 500cm3 volume. [•] He/DPA value in HFTM is very similar as the value of the DEMO first wall. [•] Neutron flux gradient in HFTM center rigs is less than 10%/cm. [Copyright &y& Elsevier]

Abstract: This work presents neutronic analyses to support the IFMIF target and test cell (TTC) design in the framework of the Broader Approach activities. A very detailed Monte Carlo geometry model of IFMIF TTC based on the modular TTC concept was prepared directly from a CAD model by using the McCad conversion software which has been developed at KIT. The Monte Carlo code McDeLicious, which is an enhancement to MCNP5, was utilized and nuclear heating, displacement damage and gas production rates in the TTC vessel wall were calculated. The calculation result shows that there are two prominent peaks; downstream of the test modules due to the high energy neutron contribution for gas productions and upstream due to neutron back-streaming along the beam ducts. The result suggests it is very important in the neutronic analysis to consider the detailed configuration of TTC and test modules. The dose rate distribution during operation has been assessed for the rooms adjacent to TTC across thick surrounding walls. The necessary thickness for the shielding walls has been examined. The result demonstrates the substantial improvement in the shielding capability for the top access cell with the present TTC design. [Copyright &y& Elsevier]

Abstract: The International Fusion Material Irradiation Facility (IFMIF) is designed to study and qualify structural and functional materials which shall be used in future fusion nuclear power plants. During the current engineering validation and engineering design activities (EVEDA) phase the development of e.g. an optimized layout and arrangement of the cells (Access Cell, Test Cell, and Test Module Handling Cells) is of major interest. After defining different functions for the individual cells like e.g. large scale/fine scale disassembling of test modules a first layout has been developed. This design followed requirements like having a minimum of carrier changes to avoid sources of failures. On the other hand it has had to be a compact arrangement of cells due to restrictions from plant layout. A row of changes of transfer direction, and different crane systems were the consequence. Constructive discussion with project team results in the statement, that for reasons of being reliable and fast, layout and arrangement of cells goes first, plant layout then will follow. The chance for big improvements was taken and the result was a simplified design with strong reduced number of functional elements, and increased reliability and speed. [Copyright &y& Elsevier]