The IFMIF-DONES Test Systems (TS) gather the experimental facilities offered by the plant, as well as the ancillary systems providing supplies and services both to those facilities and the irradiation modules, the latter ones belonging to the TS, although being excluded from the scope of this article. The irradiation modules gather any system that will be irradiated behind the lithium target inside the Test Cell (TC). Therefore, the Test Cell also houses the liquid Li target and the stripping reaction held between the latter and the D+ beam. The Test Cell is described in section 2, addressing as well some detail (section 2.1) about transversal key aspects like safety, RAMI, maintenance and others, although the safety aspects are collected in a dedicated part (section 5). The vacuum vessel is described in sections 2.2.1 and 2.2.3, relevant outputs from seismic, thermo-structural and fluido-dynamics analyses being as well provided. The shielding blocks are described in section 2.2.2, the lining part covering the building cavity filled in section 2.2.4, the floor in section 2.2.5, and the uppermost part in section 2.2.6. Section 3 is fully dedicated to the Test Systems Ancillaries, a summary description being included for each of thesubsystems, as well as an overview of their functional requirements. Section 4 provides a functional description of the different facilities for complementary experiments, apart from the TC. Section 5 is focused on safety issues applicable not only to the TC but to all the test systems included in the present article. Next, the current guidelines are given for the alignment (section 6) of the in-vessel systems and the integrated commissioning inside the TC (section 7). Finally, section 8 collects the main conclusions about the current status of the design of the Test Systems, irradiation modules excluded.

ITER needs a Disruption Mitigation System (DMS) for protection from the consequences of plasma disruptions during high-power operation. The current DMS for ITER is based on the Shattered Pellet Injection (SPI) technology. This works on the basic principle of a cryogenic pipe gun with around a half-meter-long acceleration barrel. It is important to avoid any contact between the pellet and the internal surfaces of the flight line to minimize the risk of premature pellet breakage. Therefore, the internal dimensions of the flight tube of the SPI are relatively large compared to the pellet hence providing a bypass for propellant gas resulting in a significant quantity arriving in the plasma ahead of the pellet. This will cause an undesirable instability in the plasma and compromise the effectiveness of disruption mitigation. The described events appear on a scale of a few milliseconds. One possible solution for this issue could be using a fast-acting shutter in the flight line, which will close after the pellet has passed through to hold back the propellant gas. Due to the environmental requirements, the shutter needs to close an approximately 40 mm aperture within a few ms, the shutter has limited space and limited access and acts under a magnetic field, therefore it should endure a high number of cycles and should perform well in a very demanding situation. This paper describes the optioneering study of the shutter and possible solutions for the demanding criteria. The laboratory testing of the Electromechanical Test Bench and the Prototype design are also detailed in separate papers.

The International Fusion Materials Irradiation Facility—DEMO Oriented Neutron Source (IFMIF-DONES) is a facility currently being built in Granada (Spain). It is an accelerator-driven intense neutron source designed for the study and qualification of structural materials under severe irradiation condition of a neutron field with an energy spectrum similar to the one present in a fusion power reactor. IFMIF-DONES consists of complex systems and massive components that need to be assembled and maintained on site. For several of them, it is required to perform maintenance, inspection and monitoring tasks over many years in a hostile environment and in an efficient, safe, and reliable manner. The maintenance of IFMIF-DONES systems and components, located mainly in the Test Systems, Lithium Systems, and Accelerator Systems, is classified as a remote handling (RH) 1st class activity. Over the last 5 years, much progress has been made in the definition of the maintenance activities to be performed for such a facility. The main achievements include: the definition of the RH maintenance requirements; implementation of the maintenance strategy; classification of components from the maintenance point of view; the development of the maintenance procedures and the design of the RH system (RHS). This latter system comprises the whole set of RH equipment and tooling for the execution of the maintenance tasks. In addition, a wide experimental program is ongoing to validate the RH maintenance operations and the custom and special purpose devices used to implement them. In this paper, an overview of the present status of the IFMIF-DONES RHS design is given together with a description of the validation activities, either underway or planned in the next coming years, for the RH maintenance of various systems and components of the facility.

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.

The mission of the DEMO Oriented Neutron Source (DONES) programme is to develop a database of fusion-like neutron irradiation effects in the materials required for the construction of the DEMOnstration Fusion Power Reactor (DEMO) for benchmarking of radiation response of materials. To achieve this objective, an International Fusion Materials Irradiation Facility (IFMIF)-DONES facility will be built to get irradiation conditions comparable to those in the first wall of a fusion power reactor. The broad energy distribution neutron flux covering the typical spectrum of a (d–t) fusion reactor will be generated through Li(d,n) nuclear reactions that takes place when a deuteron beam impacts a liquid Li target. The special characteristics of DONES Programme, together with the few existing references in the field, the number of research units participating, and the variety of engineering disciplines involved, make the project management of IFMIF-DONES an extraordinary challenge. Standard management practices cannot be used directly due to the inherent complexity of this facility. A great deal of modelling and customisation is necessary to provide a suitable solution for IFMIF-DONES unique requirements. The aim is none other than to achieve the traditional objectives of time, cost, quality and safety, maximising stakeholder’s satisfaction. This paper describes the management approach followed by the DONES Programme, explaining the main project structures, their evolution and the future paradigm in what we understand should be a flexible and adaptable project organisation.