Sara Bortot

RESEARCH OUTPUT

 

[1]    J. Wallenius, S. Bortot, “A small lead-cooled reactor with improved Am-burning and non-proliferation characteristics”, In: Annals of Nuclear Energy, 2018 [submitted].

[2]    J. Wallenius, S. Qvist, I. Mickus, S. Bortot, P. Szakalos, J. Ejenstam, “DESIGN OF SEALER, A VERY SMALL LEAD-COOLED REACTOR FOR COMMERCIAL POWER PRODUCTION IN OFF-GRID APPLICATIONS”, In: Nuclear Engineering and Design, 2018 [submitted].

[3]    S. Bortot, E. Suvdantsetseg, J. Wallenius, “BELLA: a multi-point dynamics code for safety-informed design of fast reactors”, In: Annals of Nuclear Energy, 85, pp. 228-235, November 2015.

[4]    J. Wallenius, E. Suvdantsetseg, S. Bortot, M. Jolkkonen, M. Pukari, A. Claisse, P. Olsson, J. Ejenstam, P. Szakalos, “ELECTRA: A Lead Cooled Reactor for Training and Education”, In: Problems of Atomic Science and Technology. Series: "Nuclear and Reactor Constants", 4, pp. 4-10, 2015.

[5]    P. Saracco, S. Bortot, A. Cammi, S. Lorenzi, S. Dulla, P. Ravetto, A. Rebora, “An intrinsically safe facility for forefront research and training on nuclear technologies - Kinetics and dynamics”, In: Physics The European Physical Journal Plus, 129, 4, 72, 2014.

[6]    M. Ripani, S. Frambati, L. Mansani, M. Bruzzone, M. Reale, S. Monti, M. Ciotti, M. Barbagallo, N. Colonnae, A. Celentano, M. Osipenko, G. Ricco, P. Saracco, C.M. Viberti, O. Frasciellog, P. Boccaccio, J. Esposito, A. Lombardig, M. Maggiore, L. Piazza, G. Prete, R. Alba, L. Calabretta, G. Cosentino, A. Del Zoppo, A. Di Pietro, P. Figuera, P. Finocchiaro, C. Maiolino, D. Santonocito, M. Schillaci, A. Kostyukov, A. Cammi, S. Bortot, S. Lorenzi, M. Ricotti, S. Dulla, P. Ravetto, A. Rebora, D. Chiesa, M. Clemenza, E. Previtali, “Study of a Low-power, Fast-neutron-based ADS”, In: Physics Procedia, 60, pp. 54-60, 2014.

[7]    M. Ripani, S. Frambati, L. Mansani, M. Bruzzone, M. Reale, S. Monti, M. Ciotti, M. Barbagallo, N. Colonna, A. Celentano, M. Osipenko, G. Ricco, P. Saracco, C.M. Viberti, O. Frasciello, P. Boccaccio, J. Esposito, A. Lombardi, M. Maggiore, L.A.C. Piazza, G. Prete, R. Alba, L. Calabretta, G. Cosentino, A. Del Zoppo, A. Di Pietro, P. Figuera, P. Finocchiaro, C. Maiolino, D. Santonocito, M. Schillaci, D. Chiesa, M. Clemenza, E. Previtali, M. Sisti, A. Kostyukov, A. Cammi, S. Bortot, S. Lorenzi, M.E. Ricotti, S. Dulla, P. Ravetto, G. Lomonaco, A. Rebora, D. Alloni, A. Borio di Tigliole, M. Cagnazzo, R. Cremonesi, G. Magrotti, S. Manera, F. Panza, M. Prata, A. Salvini, “Study of an intrinsically safe infrastructure for training and research on nuclear technologies”, In: EPJ WEB OF CONFERENCES, 79, pp. 1-9, 2014.

[8]    S. Bortot, S. Lorenzi, A. Cammi, R. Ponciroli, A.F. Della Bona, N.B. Juarez, “STABILITY ANALYSES FOR THE EUROPEAN LFR DEMONSTRATOR”, In: Nuclear Engineering and Design, 265, pp. 1238-1245, December 2013.

[9]    S. Lorenzi, R. Ponciroli, A. Cammi, S. Bortot, “DEVELOPMENT OF A CONTROL-ORIENTED SIMULATOR FOR A LFR DEMONSTRATOR”, In: Nuclear Engineering and Design, 262, pp. 319-339, September 2013.

[10] S. Lorenzi, A. Cammi, S. Bortot, R. Ponciroli, A. Moisseytsev, “ANALYTICAL MODELS FOR A SMALL LFR CORE DYNAMICS STUDIES”, In: Nuclear Engineering and Design, 254, pp. 67-88, January 2013.

[11] E. Suvdantsetseg, J. Wallenius, S. Bortot, “Optimization of the reactivity control drum system of ELECTRA”, In: Nuclear Engineering and Design, 252, pp. 209-214, November 2012.

[12] S. Bortot, C. Artioli, M.E. Ricotti, “FEASIBILITY STUDIES AND SCOPE ANALYSES FOR A SUPERSTAR DEMONSTRATOR NEUTRONICS DESIGN”, In: Fusion Science and Technology, 61, 329-337, January 2012.

[13] S. Bortot, P. Console Camprini, G. Grasso, C. Artioli, “CONCEPTUAL CORE DESIGN STUDY FOR A HIGH-FLUX LFR DEMONSTRATOR”, In: Progress in Nuclear Energy, 54, pp. 56-63, January 2012.

[14] S. Bortot, A. Cammi, C. Artioli, “DYNAMIC PERFORMANCE ASSESSMENT OF MOX AND METALLIC FUEL CORE OPTIONS FOR A GEN-IV LFR DEMONSTRATOR”, In: Progress in Nuclear Energy, 54, pp. 112-122, January 2012.

[15] S. Bortot, A. Moisseytsev, J.J. Sienicki, C. Artioli, “CORE DESIGN INVESTIGATION FOR A SUPERSTAR SMALL MODULAR LEAD-COOLED FAST REACTOR DEMONSTRATOR”, In: Nuclear Engineering and Design, 241, pp. 3021-3031, August 2011.

[16] S. Bortot, C. Artioli, “INVESTIGATION OF THE VOID REACTIVITY EFFECT IN LARGE-SIZE LEAD FAST REACTORS”, Annals of Nuclear Energy, 38, pp. 1004-1013, May 2011.

[17] S. Bortot, G. Grasso, C. Artioli, V. Peluso, M.E. Ricotti, “PRELIMINARY CORE CHARACTERIZATION OF A GENERATION IV LEAD FAST REACTOR DEMO: GOALS, DESIGN RATIONALES AND OPTIONS”, In: Energy Conversion and Management, 51, pp. 1806-1812, September 2010.

[1]    S. Bortot, J. Wallenius, K. Mikityuk, “GEN-IV FAST SPECTRUM REACTORS: E-LEARNING TEXTBOOK AND COURSE DEVELOPMENT AT KTH”, In: Proceedings of Atoms for the Future 2018 & 4th GIF Symposium, Paris, France, October 16-17, 2018 [submitted].

[2]    S. Bortot, K. Mikityuk, J. Wallenius, “GEN-IV FAST SPECTRUM REACTORS: PILOT MOOC DEVELOPMENT AT EPFL”, In: Proceedings of Atoms for the Future 2018 & 4th GIF Symposium, Paris, France, October 16-17, 2018 [submitted].

[3]    J. Wallenius, S. Bortot, I. Mickus, “Unprotected transients in SEALER: A small lead-cooled reactor for commercial power production in Arctic regions”, In: Proceedings of PHYSOR 2018: Reactors Physics paving the way towards more efficient systems, Cancun, Mexico, April 22-26, 2018.

[4]    S. Bortot, J. Wallenius, F. Di Gabriele, G. Grasso, L. Cizelj, I. Tiselj, D. Diaconu, “A proposal for a pan-European E&T programme supporting the development and deployment of ALFRED”, In: Proceedings of FR17 - International Conference on Fast Reactors and Related Fuel Cycles: Next Generation Nuclear Systems for Sustainable Development, Yekaterinburg, Russian Federation, June 26-29, 2017.

[5]    P. Larroche, S. Bortot, I. Mickus, J. Wallenius, “Design of a nitride-­fueled lead fast reactor for MA transmutation”, In: Proceedings of FR17 - International Conference on Fast Reactors and Related Fuel Cycles: Next Generation Nuclear Systems for Sustainable Development, Yekaterinburg, Russian Federation, June 26-29, 2017.

[6]    S. Bortot, I. Mickus, J. Wallenius, “Preliminary Safety Performance Assessment of ESFR CONF-­2 Sphere-pac‐Fueled Core”, In: Proceedings of FR17 - International Conference on Fast Reactors and Related Fuel Cycles: Next Generation Nuclear Systems for Sustainable Development, Yekaterinburg, Russian Federation, June 26-29, 2017.

[7]    J. Wallenius, S. Qvist, S. Bortot, I. Mickus, J. Ejenstam, P. Szakalos, “SEALER, a small lead-cooled reactor for power production in the Canadian Arctic”, In: Proceedings of FR17 - International Conference on Fast Reactors and Related Fuel Cycles: Next Generation Nuclear Systems for Sustainable Development, Yekaterinburg, Russian Federation, June 26-29, 2017.

[8]    I. Mickus, S. Bortot, J. Wallenius, “Preliminary TRANSIENT ANALYSES OF SEALER”, In: Proceedings of FR17 - International Conference on Fast Reactors and Related Fuel Cycles: Next Generation Nuclear Systems for Sustainable Development, Yekaterinburg, Russian Federation, June 26-29, 2017.

[9]    J. Wallenius, I. Mickus, S. Qvist, S. Bortot, “SEALER: A small lead-cooled reactor for power production in the Canadian Arctic”, In: 4th International Technical Meeting on Small Reactors (ITMSR-4), Ontario, Canada, November 2-4, 2016.

[10] S. Bortot, F. Alvarez-Velarde, E. Fridman, I.G. Crusado, N.G. Herranz, D. Lopez, K. Mikityuk, A.L. Panadero, S. Pelloni, A. Ponomarev, P. Sciora, A. Seubert, H. Tsige-Tamirat, A. Vasile, "European benchmark on the ASTRID-like low-void-effect core characterization: neutronic parameters and safety coefficients", In: Proceedings of ICAPP 2015, Nice, France, May 03-06, 2015.

[11] S. Pelloni, M. Aufiero, S. Bortot, J. Krepel, K. Mikityuk, A.L. Panadero, A. Pautz, P. Sciora, "Sodium Void Map Preparation for the Safety Analysis of Sodium-cooled Fast Reactors by Using the Monte Carlo Code Serpent", In: Proceedings of ICAPP 2015, Nice, France, May 03-06, 2015.

[12] J. Krepel, S. Pelloni, S. Bortot, A.L. Panadero, K. Mikityuk, "Mapping of Sodium Void Worth and Doppler Effect for Sodium-cooled Fast Reactor", In: Proceedings of ICAPP 2015, Nice, France, May 03-06, 2015.

[13] W. Maschek, L. Andriolo, C. Matzerath Boccaccini, F. Delage, S. Bortot, J. Wallenius, A. Del Nevo, C. Parisi, G. Abbate, D. Schmitt, “Safety Analyses for Sodium-Cooled Fast Reactors with Pelletized and Sphere-packed Oxide Fuels within the FP-7 European Project PELGRIMM”, In: Proceedings of ICAPP 2015, Nice, France, May 03-06, 2015.

[14] J. Wallenius, S. Bortot, “SEALER: A VERY SMALL LEAD COOLED FAST REACTOR FOR COMMERCIAL ENERGY PRODUCTION IN OFF-GRID COMMUNITIES”, In: Proceedings of the 3rd International technical Meeting on Small Reactors, Ottawa, Canada, November 5-7, 2014.

[15] S. Bortot, S. Pelloni, K. Mikityuk, “METHODOLOGY ASSESSMENT FOR THE EVALUATION OF THE COOLANT VOID WORTH IN SODIUM FAST REACTORS WITH A LOW VOID EFFECT CORE DESIGN”, In: Proceeding of PHYSOR 2014 – International Topical Meeting on Advances in Reactor Physics, Kyoto, Japan, September 28–October 3, 2014.

[16] J. Wallenius, S. Bortot, E. Suvdantsetseg, “ELECTRA-FORTE, A REALLY SMALL SMR FOR THE CANADIAN MARKET”, In: Proceedings of the 2nd ANS SMR 2013 Conference, Washington, DC, USA, November 10-14, 2013.

[17] S. Bortot, J. Wallenius, E. Suvdantsetseg, S. Pelloni, “MODELING ISSUES IN SMALL HLMC FAST REACTORS: ELECTRA CASE STUDY”, In: Proceedings of the 2nd ANS SMR 2013 Conference, Washington, DC, USA, November 10-14, 2013.

[18] J. Wallenius, E. Suvdantsetseg, S. Bortot, M. Jolkkonen, M. Pukari, J. Ejenstam, P. Szakalos, R. Thiele, A. Claisse, K. Johnson, C. Ekberg, “ELECTRA-FCC: A Swedish R&D centre for Generation IV systems”, In: Proceedings of the International Conference on Fast Reactors and Related Fuel Cycles: Safe Technologies and Sustainable Scenarios (FR13), Paris, France, March 4-7, 2013.

[19] S. Bortot, E. Suvdantsetseg, J. Wallenius, A. Della Bona, “A MATHEMATICAL MODEL FOR ELECTRA TRANSIENT ANALYSES: DEVELOPMENT AND BENCHMARK”, In: Proceedings of the International Conference on Fast Reactors and Related Fuel Cycles: Safe Technologies and Sustainable Scenarios (FR13), Paris, France, March 4-7, 2013.

[20] E. Suvdantsetseg, S. Bortot, J. Wallenius, “EVALUATION OF THE NEUTRON GENERATION TIME IN ELECTRA”, In: Proceedings of the International Conference on Fast Reactors and Related Fuel Cycles: Safe Technologies and Sustainable Scenarios (FR13), Paris, France, March 4-7, 2013.

[21] S. Frambati, L. Mansani, M. Bruzzone, M. Reale, S. Monti, M. Barbagallo, A. Celentano, M. Osipenko, G. Ricco, P. Saracco, P. Boccaccio, J. Esposito, A. Lombardi, M. Maggiore, L. Piazza, G. Prete, R. Alba, L. Calabretta, G. Cosentino, A. Del Zoppo, A. Di Pietro, P. Figuera, P. Finocchiaro, C. Maiolino, D. Santonocito, A. Cammi, S. Bortot, S. Lorenzi, S. Dulla, P. Ravetto, G. Lomonaco, A. Rebora, D. Chiesa, M. Clemenza, E. Previtali, M. Sisti, D. Alloni, A. Borio di Tigliole, M. Cagnazzo, R. Cremonesi, G. Magrotti, S. Manera, F. Panza, M. Prata, A. Salvini, “Study of an intrinsically safe infrastructure for training and research on nuclear technologies”, In: Proceedings of the 3rd European Energy Conference - E2C 2013, 2013.

[22] S. Bortot, J. Wallenius, E. Suvdantsetseg, A. Della Bona, S. Lorenzi, “ELECTRA Core Dynamics and Stability Analyses”, In: Proceedings of the European Nuclear Conference (ENC 2012), Manchester, United Kingdom, December 9 -12, 2012.

[23] M. Ripani, S. Frambati, L. Mansani, M. Bruzzone, M. Reale, S. Monti, M. Ciotti, M. Barbagallo, N. Colonna, A. Celentano, C.M. Viberti, M. Osipenko, G. Ricco, P. Saracco, O. Frasciello, P. Boccaccio, J. Esposito, A. Lombardi, M. Maggiore, L. Piazza, G. Prete, R. Alba, L. Calabretta, G. Cosentino, A. Del Zoppo, A. Di Pietro, P. Figuera, P. Finocchiaro, C. Maiolino, D. Santonocito, M. Schillaci, A. Kostyukov, A. Cammi, S. Bortot, S.Lorenzi, M. Ricotti, S. Dulla, P. Ravetto, A. Rebora, D. Chiesa, M. Clemenza, E. Previtali, M. Sisti, D. Alloni, A. Borio di Tigliole , M. Cagnazzo, R. Cremonesi, G. Magrotti, S. Manera, F. Panza, M. Prata, A. Salvini, “Study of a low-power, fast-neutron-based ADS”, In: Proceedings of the Union of Compact Accelerator-Driven Neutron Sources (UCANS) III, Bilbao, Spain, July, 31 - August 3, 2012.

[24] R. Ponciroli, S. Bortot, S. Lorenzi, A. Cammi, “DEVELOPMENT OF AN OBJECT-ORIENTED DYNAMICS SIMULATOR FOR A LFR DEMO”, In: Proceedings of the International Congress on Advances in Nuclear Power Plants (ICAPP 2012), Chicago, IL, USA, June 24-28, 2012.

[25] S. Lorenzi, S. Bortot, R. Ponciroli, A. Cammi, “EVALUATION OF THE COOLANT REACTIVITY COEFFICIENT INFLUENCE ON THE DYNAMIC RESPONSE OF A SMALL LFR SYSTEM”, In: Proceedings of PHYSOR 2012 – Advances in Reactor Physics, Knoxville, TN, USA, April 15-20, 2012.

[26] S. Bortot, S. Lorenzi, A. Cammi, R. Ponciroli, A. Della Bona, N.B. Juarez,  “DYNAMICS AND STABILITY ANALYSES OF THE EUROPEAN LFR DEMONSTRATOR ALFRED”, In: Technical Meeting on Fast Reactor physics and technology, Kalpakkam, India, November 14-18, 2011.

[27] S. Bortot, A. Cammi, S. Lorenzi, R. Ponciroli, “MODELING APPROACHES FOR DYNAMIC ANALYSES OF INNOVARIVE SMRs COMPACT STEAM GENERATORS”, In: TRANSACTIONS of the American Nuclear Society, Embedded Topical Meeting of the ANS Winter Meeting “1st Annual ANS SMR 2011 Conference”, Washington, DC, USA, October 30 - November 3, 2011.

[28] S. Bortot, C. Artioli, A. Cammi, S. Lorenzi, R. Ponciroli, “SAFETY ISSUES AFFECTING THE FEASIBILITY OF AN EARLY HIGH-FLUX LFR TECHNOLOGY DEMONSTRATOR”, In: TRANSACTIONS of the American Nuclear Society, ANS Winter Meeting, Washington, DC, USA, October 30 - November 3, 2011.

[29] S. Bortot, G. Aliberti, A. Cammi, “ON THE APPLICATION OF NEUTRON KINETICS MODELS FOR A SMALL LFR CORE TRANSIENT ANALYSES”, In: TRANSACTIONS of the American Nuclear Society, ANS Annual Meeting, Hollywood, FL, USA, June 26-30, 2011.

[30] S. Bortot, C. Artioli, M. Ricotti, “FEASIBILITY STUDIES AND SCOPE ANALYSES FOR THE SUPERSTAR PRECONCEPTUAL CORE DESIGN”, In: Proceedings of the 15th International Conference on Emerging Nuclear Energy Systems (ICENES 2011), San Francisco, CA, USA, May 15-19, 2011.

[31] S. Bortot, A. Cammi, S. Lorenzi, “AN ANALYTICAL MODEL FOR THE STUDY OF A SMALL LFR CORE DYNAMICS: DEVELOPMENT AND BENCHMARK”, In: Proceedings of the International Conference on Mathematics and Computational Methods applied to Nuclear Science and Engineering (MC 2011), Rio de Janeiro, Brazil, May 8-12, 2011.

[32] S. Bortot, A. Cammi, S. Lorenzi, “IMPACT OF LINEAR AND NON-LINEAR KINETICS MODELS ON A SMALL LFR CORE DYNAMICS”, In: Proceedings of the International Congress on Advances in Nuclear Power Plants (ICAPP 2011), Nice, France, May 2-5, 2011.

[33] J.J. Sienicki, A. Moisseytsev, S. Bortot, Q. Lu, “SUPERSTAR: AN IMPROVED NATURAL CIRCULATION LEAD-COOLED SMALL MODULAR FAST REACTOR FOR INTERNATIONAL DEPLOYMENT”, In: Proceedings of the International Congress on Advances in Nuclear Power Plants (ICAPP 2011), Nice, France, May 2-5, 2011.

[34] S. Bortot, P. Console Camprini, G. Grasso, C. Artioli, “DESIGN STUDY ON A METALLIC FUEL CORE OPTION FOR A GEN-IV LFR DEMO”, In: TRANSACTIONS of the American Nuclear Society, ANS Winter Meeting, Las Vegas, NV, USA, November 7-11, 2010.

[35] S. Bortot, A. Cammi, P. Console Camprini, C. Artioli, R. Ghazy, M.E. Ricotti, “TRANSIENT EVALUATION OF A GEN-IV LFR DEMONSTRATION PLANT THROUGH A LUMPED PARAMETER ANALYSIS OF COUPLED KINETICS AND THERMAL-HYDRAULICS”, In: Proceedings of the 2010 International Congress on Advances in Nuclear Power Plants (ICAPP 2010), San Diego, CA, USA, June 13-17, 2010.

[36] S. Bortot, G. Aliberti, “APPLICATION OF THE ERANOS KIN3D MODULE FOR A GEN-IV LFR DEMO KINETICS ANALYSIS”, In: Proceedings of the European Nuclear Conference (ENC 2010), Barcelona, Spain, 30 May – 2 June, 2010.

[37] S. Bortot, A. Cammi, C. Artioli, P. Console Camprini, R. Ghazy, “A SIMPLIFIED MODEL FOR A PRELIMINARY STUDY OF THE DYNAMIC BEHAVIOUR OF A SMALL GEN IV LFR DEMO”, In: Proceedings of the 18th International Conference on Nuclear Engineering (ICONE18), Xi’an, China, May 17-21, 2010.

[38] S. Bortot, P. Console Camprini, G. Grasso, C. Artioli, S. Monti, “CONCEPTUAL CORE DESIGN OF A GENERATION IV LFR DEMONSTRATION PLANT”, In: Proceedings of PHYSOR 2010 – Advances in Reactor Physics to Power the Nuclear Renaissance, Pittsburgh, PN, USA, May 9-14, 2010.

[39] S. Bortot, M.E. Ricotti, P. Console Camprini, G. Grasso, C. Artioli, V. Peluso, “FEEDBACK COEFFICIENT EVALUATION FOR AND ADVANCED LFR DEMONSTRATIVE REACTOR”, In: Proceedings of the International Conference Nuclear Energy for New Europe (NENE 2009), Bled, Slovenia, September 19-21, 2009.

[40] S. Bortot, G. Grasso, C. Artioli, V. Peluso, M.E. Ricotti, “APPROACH TO A PRELIMINARY CORE CHARACTERIZATION OF A GENERATION IV LEAD FAST REACTOR DEMONSTRATION PROJECT: GOALS AND RATIONALES”, In: Proceedings of the 14th International Conference on Emerging Nuclear Energy Systems (ICENES 2009), Ericeira, Portugal, 29 June - 3 July, 2009.

[41] S. Bortot, C. Artioli, “PRELIMINARY CORE CHARACTERIZATION FOR AN ELSY-ORIENTED DEMONSTRATIVE REACTOR”, In: Proceedings of the Annual International Conference on Sustainable Development through Nuclear Research and Education (Nuclear 2009), Piteşti, Romania, May 27-29, 2009.

[42] S. Bortot, C. Artioli, V. Peluso, R. Ghazy, M. Sarotto, M.E. Ricotti, “DETERMINISTIC AND STOCHASTIC APPROACH FOR A VOID REACTIVITY EFFECT EVALUATION: application to a Generation IV Lead Fast Reactor (LFR)”, In: Proceedings of the International Conference on Mathematics, Computational Methods & Reactor Physics (M&C 2009), Saratoga Springs, NY, USA, May 3-7, 2009.

 

[1]    M. Aufiero, S. Bortot, A. Cammi, S. Lorenzi, R. Ponciroli, M.E. Ricotti “Definizione delle caratteristiche richieste ad un modulo di termomeccanica in un codice multifisica di dinamica tridimensionale per reattori termici”, Report RdS/2011/366 (2011).

[2]    G. Grasso, M. Adorni, W. Ambrosini, D. Araneo, M. Aufiero, S. Bortot, A. Cammi, M. Cherubini, P. Console Camprini, E. Coscarelli, F. D’Auria, S. Dulla, S. Lorenzi, D. Mattioli, E. Molfese, D. Mostacci, R. Ponciroli, P. Ravetto, M.E. Ricotti, M. Sumini, F. Teodori, F. Terzuoli, “Studio di fattibilità per lo sviluppo di un modello multi-fisica (neutronica, termoidraulica e termomeccanica) di dinamica spaziale di nocciolo: rapporto di analisi della codicistica esistente a supporto dello sviluppo di uno strumento di dinamica spaziale di nocciolo”, Report RdS/2011/364 (2011).

[3]    S. Bortot, A. Cammi, S. Lorenzi, R. Ponciroli, “Development of a Dynamic Simulator for a LFR DEMO”, Report RdS/2011/49 (2011).

[4]    S. Bortot, A. Cammi, P. Console Camprini, C. Artioli, “Sviluppo di un modello di dinamica di nocciolo per un DEMO LFR”, Report RdS/2010/110 (2010).

[5]    J. Sienicki, S. Bortot, A. Moisseytsev, Q. Lu, G. Aliberti, “Status Report on LFR Demonstrator Development”, Report ANL-FCRD-135 (2010).

[6]    G. Grasso, P. Console Camprini, S. Bortot, C. Artioli, C. Petrovich, S. Monti, F. Rocchi, M. Sumini, M.E. Ricotti, “Static-dynamic demo core characterization”, Report ENEANNFISS-LP3–003 (2010).

[7]    S. Bortot, “Preliminary proposal for an ELSY-oriented technology demonstration project (DEMO): pre-conceptual design options”, Report ENEA-MSE FPN-P9LU-041 (2009)

 

RESEARCH INTERESTS AND SCIENTIFIC EXPERTISE

SCIENTIFIC AREA, MOTIVATION and RESEARCH OBJECTIVES

In order to tackle climate change, the European Union has committed to reduce its greenhouse gas emissions by 80 % until 2050. The International Energy Agency (IEA) foresees nuclear power to constitute an important means to reach this objective.

Both international and Swedish research on nuclear technology conducted in the last years has focused on advanced reactor designs that will meet sustainability goals simultaneously with those of improved economics and high levels of safety. Indeed, great interest is currently focused on the development of the combined technologies of fast reactors and associated closed fuel cycles, due to their potential to significantly foster a more effective utilization of uranium resources (by increasing the energy output through full use of 238U), while enabling enhanced approaches to the management of high level radioactive waste through the transmutation of Minor Actinides (MAs).

This is accompanied by a renewed interest in alternative concepts for the coolant and fuel as a means by which to attain these goals: in particular, Generation-IV (Gen-IV) systems cooled by liquid metals are particularly well suited for the implementation of defense-in-depth safety approaches due to a number of favorable properties of such coolants. Moreover, the opportunity of modularization may constitute a game-changer also for European utilities, as the development of advanced (very) Small Modular Reactors (SMRs) would allow to meet the revised safety directives of Euratom at a considerably lower regulatory and financial risk.

Since the time of my Ph.D., my research interests and scientific activities have been primarily focused on Gen-IV Lead-cooled Fast Reactor (LFR) and Sodium-cooled Fast Reactor (SFR) design (i.e., core design and primary system design) and analysis (static and dynamic system analysis, safety assessment). Such research has constituted the basis upon which I have developed the current “Gen-IV Reactors” M.Sc. course at the Royal Institute of Technology (KTH).

LFR Core Design and Analysis

In 2004, the LFR Provisional System Steering Committee selected two pool-type reactor concepts as candidates for international cooperation and joint development in the Gen-IV International Forum (GIF) framework: the American Small Secure Transportable Autonomous Reactor (SSTAR), and the European Lead-cooled SYstem (ELSY). At a technical level, follow-on LFR development was carried out within the 7th EC Framework Programme within the Lead-cooled European Advanced DEmonstration Reactor (LEADER) project, whose main objectives were to finalize the design of a large size LFR and to develop the conceptual design of a downscaled demonstrator.

In 2008, I undertook a Ph.D. project aimed at the development of two different LFR demonstrators targeting two diverse aims, reflecting the significant differences between the ELSY and SSTAR missions and designs. The first, named DEMO, was based upon the ELSY reference configuration and was aimed to both prove the viability of technology to be implemented in a first-of-a-kind industrial power plant, and serve as an irradiation facility for accelerated fuels and materials testing, thus requiring a high neutron fast flux.

The second consisted in a first-of-a-kind demonstration of an improved, modular, natural circulation-cooled STAR, named the SUstainable Proliferation-resistance Enhanced Refined Secure Transportable Autonomous Reactor (SUPERSTAR), intended for international or remote deployment, and with features for near-term realization - as opposed to the ELSY-based DEMO -, and therefore consisting in a short-term deployable, long-life LFR aimed at serving as a transportable nuclear battery.

I developed two conceptual core configurations for DEMO - with both MOX and metallic fuel alternative options - and SUPERSTAR: a preliminary broad-spectrum analysis of the technical issues that would accompany an early LFR demonstration was first performed, in order to identify a set of general objectives and requirements. Subsequently, an a priori core design methodology was set up under the supervision of Dr. Carlo Artioli and Eng. Luciano Cinotti, in their quality as my Ph.D. supervisors, and applied to establish a number of geometrical parameters on the basis of demonstration goals and technological constraints. Afterwards, scoping analyses were performed, followed by optimization studies leading to the reference core configurations for both DEMO and SUPERSTAR. A complete neutronics characterization, involving fuel cycle calculations and evaluation of reactivity coefficients and kinetic parameters (required for the subsequent study of core and primary system dynamics) was consequently accomplished.

Once established a core configuration for the two demonstrators, preliminary thermal-hydraulic (T/H) analyses were performed to verify a posteriori that safety limits were respected and postulated criteria were fulfilled.

The investigation of DEMO and SUPERSTAR dynamic behavior was finally undertaken. Calculations were carried out using a first-principle analytical model ad hoc developed (later named BELLA), as well as the SAS4A/SASSYS-1 Liquid Metal Reactor Code System. Core and primary loop models were implemented, and the reactors’ transient response following postulated accident initiators was studied, along with their stability and dynamic performance in the case of MOX and metallic fuel cores.

My Ph.D. research resulted in the conceptual design of DEMO (300 MWth LFR), which became the predecessor of the Advanced Lead-cooled Fast Reactor European Demonstrator (ALFRED). Moreover, SUPERSTAR demonstrated the feasibility of such a reactor concept in the near future (i.e., based on available technology and relying on natural circulation cooling), becoming a reference for subsequent micro reactor and (v)SMR designs, such as the European LEad-Cooled TRAining reactor (ELECTRA) and the SwEdish Advanced LEad Reactor (SEALER).

During my post-doc at KTH in 2012, I initiated the safety analyses of ELECTRA, a very small (0.5 MWth), self-regulating LFR, and, within the supervision of a Ph.D. student, contributed to the design and optimization of the reactor’s reactivity control system, introducing technical solutions specifically conceived for space reactor applications and assessing the primary system dynamics and stability.

SFR Safety Assessment

Regarding my experience in the field of SFR safety analyses, I have been working on both the Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID) during my post-doc at the Paul Scherrer Institut (PSI), under the supervision of Dr. Mikityuk, and on the European Sodium Fast Reactor (ESFR) safety assessment within the EU Project PELGRIMM while back at KTH.

As far as the former is concerned, I coordinated a European benchmark and contributed by performing a comprehensive deterministic characterization of the ASTRID core at full power (operating conditions), involving the calculation of static neutronic and kinetic parameters, reactivity coefficients and control system. Concerning the latter, I developed the ESFR primary system multi-physics model, and performed unprotected transient analyses aimed at assessing the impact that the use of sphere-pac fuel would have on the reactor’s safety. As a major outcome, it was concluded that sphere-pac fuel would definitely improve the MA burning capabilities of ESFR and, in general, SFRs, but its thermo-physical properties (e.g., low thermal conductivity) - yet not critical in the case of an Unprotected Loss of Flow (ULOF) - would require additional design provisions yielding wider safety margins against technological constraints in the scenario of an Unprotected Transient OverPower (UTOP).

(v)SMR Design and Analysis

Recent experience from licensing and constructing nuclear power plants in Europe and elsewhere have revealed flaws in the ”economy of scale” approach that historically was successful in reducing the cost of nuclear generated electricity. In addition, the Fukushima Daiichi accident clearly illustrated the challenges that operations and emergency response systems and staff may face when dealing with a major nuclear accident, emphasizing the importance of inherent safety and reliable performance under extreme conditions. The aforementioned weaknesses may possibly be addressed by adopting a complementary approach in the design and commercialization of passively safe SMRs.

An effort was undertaken by the Swedish start-up company LeadCold Reactors in tight collaboration with KTH to develop SEALER, a lead-cooled SMR specifically aimed at meeting the demands for commercial power production in Arctic regions of Canada, where electricity is expensively produced using diesel generators, which account for approximately 3 % of global CO2 emissions.

During the last three years at SUPSI and KTH, I contributed to the design and safety assessment of SEALER, focusing in particular on the modeling of the heat transport and conversion systems, and relative components (e.g., very compact and high efficiency spiral tube heat exchangers), and on the detailed assessment of fuel thermo-mechanical evolution, of un-protected blockage accidents, as well as of secondary system transients.

The current design of SEALER features vessel dimensions making the reactor transportable by air, with a rated output of 3 MWe for up to 27 full power years without reloading or reshuffling of its UO2 fuel. Such characteristics allow for the inner vessel to be sealed, delaying malevolent access to the nuclear fuel and improving security. Moreover, decay heat can be removed in a completely passive manner by natural convection from the core and radiation from the primary vessel to the environment. This work set the bases for the preparation of the documentation needed for the pre-licensing of SEALER in Canada.

Tool Development for Safety Assessment