1,720,988 research outputs found
IPADeP: A Systems Engineering process for conceptual design of Tokamak sub-systems
No full textEngineering development of large-scale engineering systems is becoming increasingly knowledge-intensive and collaborative. The involvement of multiple, competing functionality requirements and lots of resources has imposed high expectations, and at the same time challenges, for achieving reliable, affordable design. In this contest, concept design stage results a complex and iterative process in which design tasks are highly interdependent. While design freedom is at its maximum in early design stage, product knowledge is only partially known initially and is changing over time. This research discusses the use of a systematic design method, the Iterative and Participative Axiomatic Design Process (IPADeP), for the early conceptual design stage of large-scale engineering systems. Systems Engineering focuses on how to design and manage complex systems over their life cycles. Both must begin by discovering the real problems that need to be resolved and identifying from the early stage of the design the main stakeholder requirements and customer needs. The Axiomatic Design (AD) has demonstrated its strength in various type of systems design. IPADeP provides a systematic methodology for applying AD theory in the conceptual design of large-scale engineering systems. The IPADeP process is an iterative and incremental, participative process, requirements driven. It aims to provide a systematic process to face the conceptual design activities minimizing the risk related to the uncertainty and incompleteness of the requirements and to improve the collaboration of multi-disciplinary design teams. IPADeP has been developed within the pre-conceptual design activities of the DEMOnstration fusion power plant sub-systems. Accordingly, the second main aim of this dissertation is to discuss and demonstrate the advantages in using IPADeP in large-scale engineering system, in particular for the applications concerning the design of fusion tokamak reactors. Indeed the development of tokamak sub-systems has to take into account interface, structural, functional requirements and multi-physics issues that can be completely known only during the development of the process. The conceptual design o DEMO divertor fixation system has been used in this research to prove the general efficacy of the methodological instruments considered in dealing systematically with the conceptual design stage of systems characterized by high levels of complexity and poor knowledge of the technologies
Maintenance study on WCLL-TBS ancillary systems in process room
No full textThe Water-Cooled Lithium Lead Test Blanket System (WCLL-TBS) is one of the European TBS candidates for being installed and operated in ITER. The ongoing activities toward the Preliminary Design Review of the WCLL-TBS Ancillary Systems include the reallocation of their units in the reserved space, also in the view of the proper execution of the maintenance activities. Starting from the available documentation (System Design Description, Process Flow Diagrams, Process and Instrumentation Diagrams), detailed 3D CAD models have been developed for two Ancillary Systems to be installed in the Process room: the Tritium Extraction System (TES) and the Tritium Accountancy System (TAS). In the Process room (PR), the largest part of the TES process units is placed inside a Glove-box, as enclosure to avoid the contamination of the room in case of radioactive release due to failure of units. Based on the expected radioactivity content, all the TAS units are placed inside the Glove-box. Maintainability studies have been performed, focusing on the preventive (i.e. planned) and corrective (i.e. required by failures) maintenance tasks on the units installed inside the Glove-box. They were based on the 3D CAD models and supported using Virtual Reality as intuitive and immersive human-computer interface. They provided insights for the iterative improvement and consolidation of the Systems design and information for the evaluation of their availability
Virtual Reality in Systems Engineering: A Case Study in ITER RNC Maintenance Operations
No full textThe present paper proposes a description of the Virtual Reality (VR) use within the System Engineering approaches. The VR is spread among different design context and for different purposes, especially during Validation and Verification phase (V&V). A case study is introduced, derived from the nuclear fusion project ITER. The scope of the work is to validate the maintainability of the Radial Neutron Camera (RNC) Ex-Port System. The RNC Ex-port system is a diagnostic tool for detection of un-collided neutrons and gain information about the plasma state. The context of this system needs precise and safe maintenance procedures due to the harsh and potentially dangerous environment. The VR method has been used for the validation of procedures. The CAD model has been adapted into the software Unity and needed scripts have been introduced. The substitution of a detector (the 4He scintillator) is taken into consideration, verifying the feasibility for one operator. The simulation led to validation of the operation with some corrections, confirming the VR as useful tool in supporting V&V phase
Maintenance Procedure on WCLL Ancillary System–Virtual Reality Application
No full textTechnologies such as Augmented Reality and Virtual Reality (AR-VR) are changing the way to design the models. These technologies prove useful across all design phases, yet their greatest application lies in supporting the entire life cycle of a system. They shine during maintenance operations and training sessions, effectively teaching operators intricate procedures. The Virtual Reality is a useful technology in the nuclear fusion field, where the immersive visualization scenarios can be applied in to simulate maintenance operation to be conducted in radioactive environment. This study was applied on the ITER Water-Cooled-Lead-Lithium Test-Blanket-Module (WCLL-TBM) ancillary systems. The performances of the virtual reality have been tested simulating an entire maintenance operation, focusing on three main parameters: i) time, crucial aspect in nuclear field where is important to reduce the exposition to the radioactive material; ii) obstacles identification, to avoid interference with other objects during maintenance operation; iii) ergonomic standard, to consider all ergonomic parameters like the mass of the object and the verify of a correct position of an operator in each single operation. A maintenance simulation has been developed through use of a Virtual Reality tool (HTC-VIVE pro-2)
Mechanical design of ITER radial neutron camera Ex-Port system
Get PDFThe Radial Neutron Camera is an ITER diagnostic designed to measure the un-collided 14 MeV and 2.5 MeV
neutrons from deuterium-tritium (DT) and deuterium-deuterium (DD) fusion reactions, through an array of
detectors covering a poloidal plasma section along collimated Lines Of Sight (LOS). It is composed by two fanshaped
collimating structures viewing the plasma radially through vertical slots in the diagnostic shielding
module of ITER Equatorial Port 1: the In-Port RNC, devoted to plasma edge coverage, and the Ex-Port RNC,
devoted to the plasma core coverage. This paper presents an overview of the mechanical design of the Ex-Port
RNC at the Preliminary Design Review (PDR) stage. The Ex-Port RNC is located in the Port Interspace and
consists of a massive shielding structure hosting the detector units and two sets of collimators lying on different
toroidal planes. The Ex-Port RNC design is presented both from the point of view of functional requirements (e.g.
LOS positions and angles, radiation shielding, weight limitations) and of manufacturability. Finally, the Ex-port
RNC structural integrity is assessed, and its design validated against the main loads and load combinations
Configuration management of the EU DEMO conceptual design data
No full textThe EUROfusion Consortium is setting up – as part of the EU Fusion Roadmap – the framework for theimplementation of the (pre)conceptual design phase of the DEMO reactor. Configuration managementneeds have been identified as one of the key elements of this framework and is the topic of this paper, inparticular the configuration of the CAD design data. The desire is to keep the definition and layout of thecorresponding systems “light weight” and relatively easy to manage, whilst simultaneously providinga level of detail in the definition of the design configuration that is fit for the purpose of a conceptualdesign. This paper aims to describe the steps followed during the definition of the configuration man-agement system of the DEMO design data in terms of (i) the identification of the appropriate productdata management system, (ii) the description of the philosophy of the configuration management of thedesign data, and (iii) the introduction of the most important enabling processes
RFLP Approach to DTT Divertor Fixation System Design Using the 3DExperience Platform
No full textThe Product Lifecycle Management (PLM) systems lead the development of a product or a system from the early concept design until the end of the life allowing the knowledge management step by step. Among these systems, the 3DExperience platform adopts a Model Based Systems Engineering (MBSE) approach and allows to implement each phase of the design in a single co-simulation environment. This platform has been chosen for the development of the Divertor Tokamak Test (DTT) facility. The DTT tokamak, under construction at ENEA site in Frascati, has the main aim to contribute to the development of a reliable solution for power exhaust in a reactor, one of the major issues in the roadmap towards the realization of a nuclear fusion power plant. The divertor is one of the most challenging systems whose requirements coming from different physics and interfaces shall be balanced. The fixation system is the interface between the vacuum vessel and the divertor cassette body whose concept design has been carried out in a PLM system. This paper deals specifically with the application of the Requirement, Functional, Logical, Physical (RFLP) approach to the DTT divertor fixation system from the requirement elicitation and definition until the preliminary physical design, implementing each phase in the 3DExperience platform
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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