Radiation Protection and Nuclear Safety is a basic skill for a nuclear engineer all over the world. This part (Safety of nuclear plants) of the course will provide knowledge of the fundamental topics involved in the safety analysis of nuclear plants (design basis and severe accidents) from both deterministic and probabilistic point of view. Main topics deal with deterministic and probabilistic methodologies necessary to assess the safety of a nuclear power plant, with reference to both design basis and severe accidents. Both analytical models and numerical simulation tools will be provided and applied to study the fundamental thermal-hydraulic phenomena and system behaviour, which are fundamental to avoid the core damage during an accidental sequence.

The aim of the Course is to meet the needs of students at graduate level, to acquire knowledge and training in safety of nuclear plants. The course also aims to provide the necessary basic tools for those who will become professionals in nuclear safety analyses. It is designed to provide both theoretical and practical training in the multidisciplinary scientific and/or technical bases of national and international recommendations and standards on nuclear safety standards, and their implementation. At the end of the course the students should be able to analize and model the phenomena occurring during accidental transients, up to severe accidents, and the safety systems apt to the reduction of the risk to the population and environment.

Good knowledge of reactor physics, nuclear power plants and single and two-phase thermal-fluid-dynamics and heat transfer.

Protection system and engineered safety features in power reactors. Deterministic analysis of Design Basis Accidents: causes, physical phenomena, simplified analytical models, characteristic time constants, time behaviour of process parameters during the accidents. Severe accidents: in-vessel and ex-vessel phenomena, fission product release from the reactor core and their removal from the containment system atmosphere. Probabilistic Risk Assessment: objectives and results of the three levels of the PRA. Development of event trees in PRA-Level 1 of nuclear reactors, containment failure modes, containment event tree. Safety problems in nuclear fusion reactors

The theoretical lectures are completed by practical parts dealing with the numerical evaluation of the time behaviour of the more relevant parameters during transients in Pressurized Water Reactors. The students are divided into groups of maximum three people; they will cooperate in order to develop the analytical model, implement it, analyse the numerical results and write a report including also the computer scripts. The reports will be evaluated and contribute to the final grade (see grading criteria). A visit to a nuclear facility may be part of the program.

Lecture slides on each topic will be provided online by the instructor. The following texts are recommended: R. A. Knief, Nuclear Engineering: Theory and technology of Commercial Nuclear Power, Hemesphere Publishing Corporation, 1992. E.E. Lewis, Nuclear power reactor safety, Wiley, New York, 1977. D. L. Hetrick, Dynamics of Nuclear Reactors, The University of Chicago Press, Chicago, 1971. G. Petrangeli, Nuclear Safety, Butterworth-Heinemann, Oxford, 2020. N.J. McCormick, Reliability and risk analysis, Academic Press, London, 1981. N.E.Todreas and M.S.Kazimi,"Nuclear systems",Vol.I ,II,Hemisphere,1990. R.T.Lahey and F.J.Moody,"The thermal-hydraulics of a boiling water reactor",American Nuclear Society, New York, 1993. L.S.Tong and J.Weisman,"Thermal analysis of pressurized water reactors", American Nuclear Society, La Grange Park,1996

Slides; Libro di testo;

Modalita di esame: Prova orale obbligatoria; Elaborato progettuale in gruppo; Prova scritta in aula tramite PC con l'utilizzo della piattaforma di ateneo;

Exam: Compulsory oral exam; Group project; Computer-based written test in class using POLITO platform;

... The exam is aimed at checking the student's knowledge about the topics listed in the official program of the course and his ability to apply the theory and the relative methods to answer questions dealing with Radiation Protection (RP) and Safety of Nuclear Plants (SNP). The exam consists of a written test with open-ended questions on the topics of the course. It aims to verify the level of knowledge and understanding of the covered topics, with particular reference to the skills specified in the "Expected learning outcomes" part. The written exam deals with two parts (one regarding the Radiation Protection and the other regarding the Safety of nuclear plants), which the student may choose to address altogether or separately in any appeal. Each part consists of two open-answer questions. Time to answer each part: 60 minutes. During the written exam, it is not allowed to keep and consult books and notebooks, nor use mobile phones. The written exam gets a grade going from 0 to 30 and it is considered "pass" when the grade is equal or higher to 18/30. The results of the written test are communicated on the portal, loading in the Materials section appropriate files with the grades, together with a date in which the students can participate to the oral discussion. The oral discussion deals with a discussion of the reports and of the personal written elaborates. The mark of the part on Safety of nuclear plants is calculated as follows: 80% of the mark of written test + 20% of the mark of the reports (which also includes the discussion). The exam is passed if a grade >18/30 is obtained in both the parts (RP and SNP). The final grade of Radiation Protection and Safety of Nuclear Plants will be the average between the mark of Radiation Protection and the one of Safety of Nuclear Plants.

Gli studenti e le studentesse con disabilita o con Disturbi Specifici di Apprendimento (DSA), oltre alla segnalazione tramite procedura informatizzata, sono invitati a comunicare anche direttamente al/la docente titolare dell'insegnamento, con un preavviso non inferiore ad una settimana dall'avvio della sessione d'esame, gli strumenti compensativi concordati con l'Unita Special Needs, al fine di permettere al/la docente la declinazione piu idonea in riferimento alla specifica tipologia di esame.