Nuclear Reactors
Research focus
The Peer review has evaluated this group as Excellent
Since 2000 the research is focused on Next Generation Reactors. In particular, on the participation to the IRIS reactor project: the Group is active since the beginning and is a co-founder together with Westinghouse, MIT and UCBerkeley (USA-NERI grant, 1999). Currently the consortium involves 20 organisations (universities, research centres, industries, utilities) from 10 countries (http://www.irisreactor.org). The Group is active on innovative safety concept and systems (co-owner of International Patent WO 02/073625 A3 on IRIS integral reactor containment and safety systems), on thermalhydraulic and thermomechanical aspects of components/systems, on safety and control issues. Thermalhydraulics: theoretical and experimental investigation of helical coil tube, modular steam generators, to identify the dynamic behavior and the effect of geometrical and T-H parameters on two-phase pressure drops, dryout, flow instability, to obtain general validity correlations and stability maps; theoretical and experimental investigation of two-phase flow, natural circulation, closed loop passive safety systems in sliding pressure configuration, for stable-unstable behavior characterization; collaboration to the study, design and future operation of an integral facility (SPES-3) for the IRIS integral testing, for NRC licensing purposes. Collaboration with: Westinghouse, University of Zagreb, ENEA, Ansaldo-Camozzi, Ansaldo Nucleare. Thermomechanics & structural dynamics: theoretical and numerical investigation on the collapse of thick tubes under external pressure, aimed at reducing their thickness with respect to existing requirements, so as to diminish the resistance given by conductivity through the metal (interaction with ASME Boiler and Pressure Vessel Code committees). Numerical analysis of the response of Nuclear Power Plants to seismic excitation, aimed at: (i) the definition of a simplified but accurate model to predict the acceleration history at the components supports, so as to reduce safety factors referring to analysis uncertainties; (ii) the assessment of soil damping influence on the component response, in order to obtain a precise definition of its effects; (iii) the definition of fragility curves for significant components, giving their probabilities of failure as function of the peak ground acceleration, also to the purpose of providing hints for a safer design Research Assessment Exercise (2003 – 2006) -- Dipartimento di Ingegneria Nucleare - CeSNEF (DIN) 16 (collaboration with: Westinghouse, ENEA, Department of Structural Engineering of the Politecnico). Safety & Control: development of a risk-informed approach to the design phase of next generation reactors (e.g. IRIS), following a “safety-by-design” strategy, the main goals being a sensible reduction of both the estimated Core Damage Frequency (CDF) and the Emergency Panning Zone (EPZ); development of object-oriented modelling for flexible and fast running simulators, for dynamic response analysis and control purposes, applicable to different reactor concepts (IRIS, reactors for space applications, ADS), adopting a model-based, predictive control strategy. Collaboration with: IAEA (participation to two Cohordinated Research Projects), Westinghouse, Univ. of Zagreb, European Space Agency, ENEA, Ansaldo Nucleare, Electronics and Information Dept. Other activities. Economics of Small-Medium reactors (IAEA Cohordinated Research Project – collaboration with Westinghouse, POLIMI-Industrial Management and Economics Dept.). LBE cooled Accelerator Driven Systems and since 2006 involvement in ELSY-European Lead-cooled SYstem project (15 EU organizations - via CIRTEN consortium). Main topics: control systems; development and validation of codes for coupled TH-neutronics study, including burnup, for sustainable cores (collaboration with LENA lab-TRIGA reactor and Ben-Gurion University); innovative fuels (nitrides) and fuel performance codes (TRANSURANUS) (collaboration with ITU-Karlsruhe). Since 2006, effort to extend the collaboration with Building Architecture from the educational to the research side: TH-CFD simulation and object-oriented modelling and control capabilities for “energy saving in buildings” studies, new analysis tools for dynamic evaluation of energy loads and for energy saving strategies.
Dipartimento di afferenza
Docenti afferenti
Full Professors
Leone Corradi Dell’Acqua
Marco Enrico Ricotti
Assistant Professors
Antonio Cammi
Lelio Luzzi