European Master of Science
in Nuclear Engineering

 

SUBJECTS FOR M.Sc THESIS WORKS

TO BE PERFORMED AT PISA UNIVERSITY

 

 

The CIRTEN (Consorzio InterUniversitario per la Ricerca Tecnologica sull'Energia Nucleare) is proposing Subjects for Thesis Works to be performed at the University of Pisa, Italy, addressed to students willing to get the EMSNE Quality Label granted by the ENEN Association.

 

Subjects are available in the following fields:

 

 

·       Nuclear Reactor Physics Applications

 

 

O   Feasibility study of a near-threshold accelerator-based BNCT facility for in-situ irradiation of tumors

TUTOR: Prof. Bruno MONTAGNINI (b.montagnini@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: BNCT (Boron Neutron Capture Therapy) is a radiation cancer therapy based on two distinct conditions: 1) a selective uptake of the tumor tissue with respect to the healthy tissue of a suitable drug loaded with boron-10; 2) the irradiation of the tumor region with a neutron flux characterized by a very specific energy spectrum. Very often the energy spectrum of the neutron source is not directly employable for treatment and a partial moderation is required in order to get an epithermal enhanced energy spectrum. This process is very expensive in terms of the neutron population. The so called “near-threshold approach” has the interesting characteristic that the energy spectrum of the produced neutrons is pretty close to that required for a correct treatment and very small spectrum shaping is then required. In this work the near threshold Li(p,n) reaction will be studied and a preliminary feasibility design of such a BNCT facility will be performed by means of Monte Carlo simulations. The possibility to use this facility to treat in-situ liver tumors or other superficial tumors like the melanoma will be also investigated.

 

·       Structural Mechanics – Nuclear

 

O   Dynamic analysis of the containment and reactor structures of an Innovative PWR in accident conditions

TUTORS: Prof. Giuseppe FORASASSI (g.forasassi@ing.unipi.it), Prof. Donato AQUARO

DURATION: 4-6 Months

DESCRIPTION: At present innovative PWRs are studied in several contexts. Among them the IRIS reactor is being designed at Westinghouse in the frame of an International Consortium including the University of Pisa. Structural mechanics, neutronics, thermal-hydraulic as well as economical aspects are considered. The proposed study deals in particular with the analysis of the response of the containment and primary loop structures to dynamic loads and their behaviour under external accidents including seismic events and airplane impact. The activity includes the setting up of appropriate numerical models and will be performed by means of up to date computer codes, analysing the alternative plant configurations in the light of their convenience and feasibility.

 

 

O   Analysis of the erosion of plasma facing components by means of molecular dynamic simulations

TUTOR: Prof. Donato AQUARO, Prof. Salvatore LANZA (d.aquaro@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The activity is developed in the frame of ITER-FEAT nuclear fusion reactor. The First Wall and the Divertor Armor are eroded due to the impact of ions, neutrals, alpha particles, as well as to the impact of the plasma disruptions in the events called ELMs (Edge Localized Modes) or VDE (Vertical Displacement Event). The erosion depends on the interactions which occur in an atomic or molecular scale. The activity aims are to obtain the characteristics values (mechanical, thermal and chemical properties) which the erosion depends on, performing molecular dynamic simulations.

 

 

·       Nuclear Reactor Safety

 

O   Analysis of dust resuspension phenomena for the ITER fusion reactor

TUTOR: Prof. Sandro PACI, Dr. Nicola FORGIONE (s.paci@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: Some of the ITER reactor challenging sequences are under analyses at ENEA FUS Frascati, CESI Milan and Pisa University in the frame of EFDA. Thermal-hydraulics as well as radiological species transport aspects are considered. The proposed study deals with the experimental and theoretical analysis of the of dust resuspension phenomena inside the vacuum vessel of a tokamak reactor. The activity will be performed making use of computer codes as ECART and FLUENT, analysing the tests performed inside the STARDUST facility located at ENEA Frascati laboratories.

 

 

·       Nuclear Reactor Thermal-hydraulics

 

O   Analysis of mixing phenomena in the atmosphere of a nuclear containment system

TUTORS: Prof. Francesco Oriolo, Prof. Sandro PACI, Dr. Nicola FORGIONE, Dr. Antonio MANFREDINI

(s.paci@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The activities for this topic will be carried in the framework of EU thematic network SARNET. The proposed study deals with the computational analysis of the of natural circulation and atmosphere mixing phenomena inside the containment system of a nuclear plant, including the effect of condensation on wall. These activity will be performed making use of a lumped parameters code as FUMO and the CFD code FLUENT, analysing the tests performed inside the TOSQAN and MISTRA experimental facilities for the OECD/CSNI ISP-47.

 

O   Experimental and computational analysis of steam condensation in the presence of air and helium mixtures for nuclear reactor applications

TUTORS: Prof. Walter AMBROSINI, Prof. Francesco ORIOLO, Dr. Nicola FORGIONE (walter.ambrosini@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The CONAN experimental facility is installed and operating at the Scalbatraio Laboratory at the University of Pisa. First series of experimental tests have been already performed and their results have been published. Additional work is anyway needed to improve instrumentation and adopt different gases as noncondensibles as well as to consider different test procedures, including transient behaviour. Also on the computational side, the use of 1D system codes, lumped parameter codes for containment analysis as well as CFD codes has been undertaken. The proposed work is focused on performing experiments with mixtures of air and helium and on predicting the observed condensation rates and other relevant parameters with CFD codes adopting different calculation methodologies.

 

O   Experimental and numerical study of natural and gas-injection enhanced circulation of molten metal for ADS reactor applications

TUTORS: Prof. Walter AMBROSINI, Prof. Francesco ORIOLO, Dr. Nicola FORGIONE (walter.ambrosini@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: Accelerator Driven Systems (ADS) are presently proposed to incinerate long lived wastes from commercial nuclear reactors by transmuting them into shorter lived radionuclides. The fluids considered to cool the subcritical cores envisaged in such reactors are the lead and bismuth eutectic or lead. An experimental facility is presently operating at the University of Pisa allowing for the study of natural and gas-injection enhanced circulation with water as working fluid. A step forward is presently considered, changing the coolant fluid to lead in order to make thermal-hydraulic analyses which could validate the relevant scaling laws. The proposed work should evaluate the feasibility of such change, by addressing the operational, measuring and safety problems related to the introduction of lead. This feasibility analysis should be made mainly on the basis of the application of thermal-hydraulic computer codes, to identify the required hardware changes and design possible test procedures.

 

O   Analysis of experiments simulating the thermal-hydraulic behaviour of IRIS steam generator

TUTORS: Prof. Walter AMBROSINI, Prof. Francesco ORIOLO, Dr. Nicola FORGIONE (walter.ambrosini@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: Downscaled experiments on the behaviour of helical coil steam generators envisaged for IRIS reactor are being performed by the Politecnico di Milano at the SIET Laboratories in Piacenza (Italy). The University of Pisa is involved in the activity mainly concerning the pre-test and the post-test simulation of experiments, to be performed by the use of the RELAP5 computer code. The proposed work should undertake the simulation, trying to reproduce the observed behaviour and identifying the margin to unstable behaviour during the considered operating conditions.

 

O   Modelling steam explosions due to the interaction between water and molten metals

TUTORS: Prof. Walter AMBROSINI, Prof. Francesco ORIOLO, Dr. Nicola FORGIONE (walter.ambrosini@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: Accelerator Driven Systems (ADS) are presently proposed to incinerate long lived wastes from commercial nuclear reactors by transmuting them into shorter lived radionuclides. The fluids considered to cool the subcritical cores envisaged in such reactors are the lead and bismuth eutectic or lead. The work should contribute with an analysis of the state-of-the-art to better focus the problems that could be encountered by the interaction of water from a heat exchanger leak with the molten coolant (lead or lead an bismuth eutectic). Suitable models and available experimental data should be revised to support conclusions about the dangers which may be faced in the proposed reactor configuration.

 

O   Title Keywords: Cathare Assessment

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The French Thermal-hydraulic system code CATHARE will be assessed against a series of experiments test performed in the (VVER NPP simulator) PSB test facility. The innovation is constituted by the use of the latest version of Cathare code and by the nature of experiments that deal with complex AM procedures. The scaling issue will be dealt based on the availability of Cathare input deck of Balakovo unit 3 VVER-1000 NPP.

 

O   Title Keywords: AP 1000 TH

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: To investigate and to optimize the transient performance of the innovative reactor, Westinghouse AP-1000 NPP, using RELAP5 and TRACE as simulation tools. The innovation is constituted by the optimisation of the new reactor design and by the use of the TRACE code. The activity will be conducted in close cooperation with Ansaldo specialists.

 

O   Title Keywords: AM [boron]

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: To investigate the accident management and related decision making, and the use of formal techniques in response to events following accidents in a VVER-1000 NPP. The innovation is constituted by the investigation of AM related to the NPP types owned by Countries that are part of the enlarged EC. Addressing the boron issue, e.g. the boron dilution caused by two-phase mixture and condensation in SG and break de-boration, already studied in PWR types reactors mainly in SBLOCA conditions, constitutes another innovation. The research will benefit of  cooperation with Russian and former East European experts and Institutions. In addition,  the main outcomes from a TACIS project, whose activities are currently in progress at UNIPI, will be exploited.

 

O   Title Keywords: CIAU Cathare

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: Large thermal-hydraulic system codes have been developed and are currently used to simulate transients behaviour in nuclear power plants. As a consequence a large effort is necessary to calculate the uncertainty and it has been recommended as a desirable capability for thermal-hydraulic system codes. The CIAU method was successfully implemented in the RELAP5 code, and the objective of the current subject is to implement the aforementioned method in the CATHARE code. The innovation is constituted by the creation of the database of error specific  for the latest version of the French code, suitable for application to DBA and BDBA conditions (including AM scenarios) as needed for the licensing process. The connection with licensing constitutes a further innovation. The research will benefit of cooperation with CEA Grenoble and with other international Cathare code users.

 

O   Title Keywords: 3D NK/TH BWRS

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: Boiling  channels  and systems in a BWR (Boiling Water Reactor) may present instability phenomena owing to the dynamic behaviour of the liquid-steam mixture used for removing the thermal power. To improve the safety systems of these reactors, it is necessary to be able to detect in a reliable way the oscillations generated in the neutron power (well known and deeply investigated problem in the last 50 years). The innovation is constituted by the use of a 3D neutron kinetics code coupled with a qualified system thermal-hydraulic code. The possibility to model one-by-one the fuel elements is exploited. Standard methods and procedures are used including perturbation analysis, qualification (based on NPP data measured in Peach Bottom) and output data processing. The coupled codes RELAP5/PARCS is used. Connections are established with Universities of Valencia and Penn State.

 

O   Title Keywords: 3D NK/TH boron

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The effect of a positive reactivity induced by a boron dilution slug through the core of a PWR reactor is investigated using the coupled 3 D Neutron Kinetics Thermal-Hydraulic system codes technique. The coupled codes RELAP5/PARCS and RELAP5/3D – NESTLE are used. The derivation and the qualification of “boron XSEC” (actually derivative of XSEC with boron content as independent variable) suitable for complex system analyses constitutes one innovation. Sensitivity studies of NPP response to boron originated transients constitute an important achievement of the thesis work. The connection with international projects (including the integration of results)  like OECD/NEA MSLB Benchmark and the EC CRISSUE-S constitutes one additional achievement for this research activity. The research activity at the time of issuing of this document is basically completed.

 

O   Title Keywords: 3D NK/TH

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The proposed subject consists in the application of the coupled 3D Neutron Kinetic Thermal-Hydraulic system codes technique for the best estimate simulation of some phenomena which may occurs in a prototype NPP in construction in Brazil. The techniques are of interest to the design optimization and the safety evaluation. Typical problems to be addressed are the control rod ejection and reactivity following typical DBA. The research might benefit of cooperation with Brazilian specialists (agreements to be finalized). The innovation is constituted by the application of the coupled techniques to a special reactor type.

 

O   Title Keywords: CFD [generic]

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The idea at the basis of the research proposal is to give a contribution to the application of the CFD techniques to the nuclear technology. The background is constituted by the IAEA/OECD Conference had in Pisa in 2002 and by results of more recent projects completed within the framework of EC and OECD. Two technical themes are of main interest: a) the mixing of cold and hot fluid needed for addressing the PTS issue and b) the RPV mixing of borated and de-borated water for calculating possible core re-criticality (or, better margins to re-criticality) following the boron dilution. The connection and the coupling between CFD and structural mechanics codes constitutes an open issue (and a potential innovation) for the proposed research. The research could benefit of contacts already established between UNIPI and CEA-Grenoble and FZR.

 

O   Title Keywords: RBMK [3D NK/TH]

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The transient performance of RBMK reactor constitutes the subject for the proposed research project. The RELAP5/3D tool including its 3D Neutron Kinetics model (NESTLE) will be adopted to investigate a series of complex accident scenarios. The innovation is constituted by the investigation of safety issues related to the RBMK owned by countries that are part of the enlarged EC and of the Russian Federation. The research will benefit of  cooperation with Russian and Lithuanian experts and Institutions. In addition, the main outcomes from a TACIS project, whose activities are currently in progress at UNIPI, will be exploited.

 

O   Title Keywords: CIAU and BEMUSE

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: The extension of the CIAU methodology to the  results of 3D neutron kinetics thermal-hydraulics calculations (CIAU-TN) already constituted the subject for a Master degree that needs some finalisation that will be pursued in the present framework. However, the main topic for the research is the establishment of an applicable version for the methodology based upon the extension of the error database and the final internal and external qualification of the method. The extension shall be based upon the availability of a few tens of ITF database (experiments and calculation results) already derived or to be derived at UNIPI. The innovation is constituted by the proof of the validity of the method also based upon the participation and managing from the side of UNIPI of the BEMUSE OECD Project. The thesis subject will also include the main findings from this project and will benefit of the related intensive international cooperation. 

 

O   Title Keywords: BE and licensing

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION: Licensing processes are performed using qualified tools and procedures. The acceptable safety margins depend on the selected approach (best estimate or conservative). Up to now (almost) all licensing authorities have considered acceptable only the conservative approach. The proposed research deals with the consistent and robust implementation of the best estimate approach into the licensing process. This requires a sound understanding of the capabilities of the computational software and of the uncertainty methods as well as of the regulatory environment and needs. The innovation is constituted by the proposal of the procedure for the application of the BE analysis methods for licensing purposes.  The research will benefit of an IAEA international conference to be held in Pisa in September 2005 and of the connected follow up. External tutors for the thesis are recognized international experts.

 

O   Title Keywords: PKL [boron system TH]

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION:The current work is dedicated to the creation of a database that includes the experimental and the calculated results concerning the tests performed in the PKL facility. These tests are related to the boron dilution in loop seal, the mechanisms of transport of de-borated plugs into the core, and (not in the experiment) the evaluation of the reactivity effect due to de-borated water in the core. The boron dilution and de-boration scenarios are important in the current safety evaluation of PWR systems with main regard to DBA situation (namely SBLOCA with ECCS available). The innovation is constituted by the quality demonstration (assessment) of the codes (Relap5 and Relap5 3D). The activity takes benefit from the international projects managed by OECD/NEA/CSNI, i.e. SETH and PKL. In this framework and international Workshop is planned in Pisa for October 2005.

 

O   Title Keywords: 3D NK/TH VVER 1000

TUTOR: Prof. Francesco D’AURIA (f.dauria@ing.unipi.it)

DURATION: 4-6 Months

DESCRIPTION:The application of coupled 3D NK/TH code techniques has been qualified by the international scientific community making reference to complex transients in Light Water Reactors, e.g. the MSLB in PWR and the BWRtt. The application of the same techniques to VVER constitutes the innovation of the present activity. The activity takes benefit from the OECD/NEA international project VVER-1000 CT and from the contacts with the Pennsylvania State University.

 

 

FURTHER INFORMATION

 

Students interested in one or more of the above subjects may send an e-mail directly to the Tutors or refer to

 

Casella di testo: Prof. Walter AMBROSINI
Università di Pisa
Facoltà di Ingegneria
Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione
Via Diotisalvi 2
56126 – PISA, Italy
Tel. ++39-050-836673
Fax ++39-050-836665
E-mail: walter.ambrosini@ing.unipi.it
Web Page: http://www2.ing.unipi.it/~d8155/

 

 

including the following information:

 

o       Name, age, nationality and address (also e-mail)

o       Home University

o       Educational background (e.g., degrees, list of successfully passed examinations)

o       Subjects of interest, to be chosen in the list reported above

o       Preferred period for developing the Thesis work

o       Preferences for accommodation (needs and maximum prices)

 

ACCOMODATION

 

Prices of student single rooms in Pisa may range from € 200 to 400 per person per month, depending on the characteristics.

 

Support for finding a suitable and cheap lodging in Pisa will be provided by the organisation.