Speaker
Tonio Pinna
(Nuclear Fusion and Safety Technologies Department (FSN-FUSTEC-TEN))
Description
Safety studies are performed in the frame of the conceptual design studies for the European DEMO reactor to assess the safety and environmental impact of design options. An exhaustive set of reference accident sequences are defined in order to evaluate plant response in the most challenging events and compliance with safety requirements. The identification of a comprehensive set of accident initiators is the first step for the definition of the reference accident sequences.
The Functional Failure Mode and Effect Analysis (FFMEA), based on a top-down approach, is a suitable methodology to define possible accident initiators when insufficient design detail is available to allow for more specific evaluation at component level. The main process, safety and protection functions related to the DEMO reactor are defined through a functional breakdown structure (FBS). Then, an exhaustive set of high level accident initiators is defined referring to loss of functions, rather than to specific failures of systems and components, overcoming the lack of detailed design information. Nonetheless reference to systems or main components is always highlighted, as much as possible, in order to point out causes and safety consequences.
Through the FFMEA a complete list of potential accident initiating events (IEs) is provided together with suggestions to improve the overall safety of the machine. From the complete list of IEs, a set of postulated initiating events (PIEs) is selected as the most representative in terms of challenging conditions for the safety of the plant.
All the four blanket concepts of the European DEMO reactor are analysed by the FFMEA and a first set of reference accident sequences are selected by a collaboration among European Research Units. The main goal of this paper is to outline the reference accident sequences selected for the four blanket concepts of DEMO.
Co-authors
Andrea Carpignano
(NEMO group, Dipartimento Energia, Politecnico di Torino, 10129 Torino, Italy)
Anna Chiara Uggenti
(NEMO group, Dipartimento Energia, Politecnico di Torino, 10129 Torino, Italy)
Dario Carloni
(Institute of Neutron Physics and Reactor Technology (INR), , Karlsruhe Institute of Technology (KIT), Herrmann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany)
Giulia Sobrero
(NEMO group, Dipartimento Energia, Politecnico di Torino, 10129 Torino, Italy)
Jane Johnston
(Culham Centre for Fusion Energy (CCFE), UKAEA, Culham Science Centre, Abingdon, Oxfordshire, OX14 3DB, United Kingdom)
Laura Savoldi
(NEMO group, Dipartimento Energia, Politecnico di Torino, 10129 Torino, Italy)
Maria Teresa Porfiri
(Nuclear Fusion and Safety Technologies Department (FSN-FUSTEC-TEN), ENEA, Frascati (Rome), Italy)
Mindaugas Vaisnoras
(Lithuanian Energy Institute, LEI, Breslaujos g. 3, LT-44403, Lithuania)
Neill Taylor
(Culham Centre for Fusion Energy (CCFE), UKAEA, Culham Science Centre, Abingdon, Oxfordshire, OX14 3DB, United Kingdom)
Sergio Ciattaglia
(EUROfusion Consortium, Boltzmannstr.2, Garching 85748, Germany)
Tonio Pinna
(Nuclear Fusion and Safety Technologies Department (FSN-FUSTEC-TEN), ENEA, Frascati (Rome), Italy)
