75 research outputs found
Uncertainty and Sensitivity Analysis for a Nuclear Power Plant Large Break Loss of Coolant Accident (LB-LOCA) in the Context of OECD BEMUSE Programme
No full textMain Results of the OECD Best Estimate Methods, Uncertainty and Sensitivity Evaluation (BEMUSE) Programme
No full textInternational Training Program in Support of Safety Analysis: 3D S.UN.COP - Scaling, Uncertainty and 3D Thermal-Hydraulics/Neutron kinetics Coupled Codes Seminars
No full textThermal-hydraulic system computer codes are
extensively used worldwide for analysis of nuclear facilities
by utilities, regulatory bodies, nuclear power plant designers
and vendors, nuclear fuel companies, research organizations,
consulting companies, and technical support organizations.
The computer code user represents a source of uncertainty
that can influence the results of system code calculations.
This influence is commonly known as the ‘user effect’ and
stems from the limitations embedded in the codes as well as
from the limited capability of the analysts to use the codes.
Code user training and qualification is an effective means for
reducing the variation of results caused by the application of
the codes by different users. This paper describes a
systematic approach to training code users who, upon
completion of the training, should be able to perform
calculations making the best possible use of the capabilities
of best estimate codes. In other words, the program aims at
contributing towards solving the problem of user effect. The
3D S.UN.COP (Scaling, Uncertainty and 3D COuPled code
calculations) seminars have been organized as follow-up of
the proposal to IAEA for the Permanent Training Course for
System Code Users. Nine seminars have been held at
University of Pisa (two in 2004), at The Pennsylvania State
University (2004), at the University of Zagreb (2005), at the
School of Industrial Engineering of Barcelona (January-
February 2006), in Buenos Aires, Argentina (October 2006),
requested by Autoridad Regulatoria Nuclear (ARN),
Nucleoelectrica Argentina S.A (NA-SA) and Comisión
Nacional de Energía Atómica (CNEA), at the College
Station, Texas A&M, (January-February 2007), in Hamilton
and Niagara Falls, Ontario (October 2007) requested by
Atomic Energy Canada Limited (AECL), Canadian Nuclear
Society (CNS) and Canadian Nuclear Safety Commission
(CNSC), in Petten, The Netherlands (October 2008) in
cooperation with the Institute of Energy of the Joint
Research Center of the European Commission (IE-JRC-EC).
It was recognized that such courses represented both a
source of continuing education for current code users and a
mean for current code users to enter the formal training
structure of a proposed ‘permanent’ stepwise approach to
user training. The 3D S.UN.COP 2008 at IE-JRC was
successfully held with the attendance of 35 participants
coming from more than 10 countries and 20 different
institutions (universities, vendors and national laboratories).
More than 30 scientists (coming from more than 10 countries
and 20 different institutions) were involved in the
organization of the seminar, presenting theoretical aspects of
the proposed methodologies and holding the training and the
final examination. A certificate (LA Code User grade) was
released to participants that successfully solved the assigned
problems. A tenth seminar will be held (October 2009) at the Royal Institute of Technology (KTH) in Amsterdam
(Sweden), involving more than 30 scientists between
lecturers and code developers
(http://dimnp.ing.unipi.it/3dsuncop/2009/index.html)
International Training Program in Support of Safety Analysis: 3D S.UN.COP — Scaling, Uncertainty and 3D Thermalhydraulics/Neutron-Kinetics Coupled Codes Seminar
No full textThermal-hydraulic system computer codes are extensively used
worldwide for analysis of nuclear facilities by utilities, regulatory
bodies, nuclear power plant designers and vendors, nuclear fuel
companies, research organizations, consulting companies, and technical
support organizations. The computer code user represents a source of
uncertainty that can influence the results of system code calculations.
This influence is commonly known as the ‘user effect’ and stems from the
limitations embedded in the codes as well as from the limited capability
of the analysts to use the codes. Code user training and qualification
is an effective means for reducing the variation of results caused by
the application of the codes by different users. This paper describes a
systematic approach to training code users who, upon completion of the
training, should be able to perform calculations making the best
possible use of the capabilities of best estimate codes. In other words,
the program aims at contributing towards solving the problem of user
effect. The 3D S.UN.COP (Scaling, Uncertainty and 3D COuPled code
calculations) seminars have been organized as follow-up of the proposal
to IAEA for the Permanent Training Course for System Code Users. Eleven
seminars have been held at University of Pisa (two in 2004), at The
Pennsylvania State University (2004), at the University of Zagreb
(2005), at the School of Industrial Engineering of Barcelona (January-
February 2006), in Buenos Aires, Argentina (October 2006), requested by
Autoridad Regulatoria Nuclear (ARN), Nucleoelectrica Argentina S.A
(NA-SA) and Comisión Nacional de Energía Atómica (CNEA), at the College
Station, Texas A&M, (January-February 2007), in Hamilton and Niagara
Falls, Ontario (October 2007) requested by Atomic Energy Canada Limited
(AECL), Canadian Nuclear Society (CNS) and Canadian Nuclear Safety
Commission (CNSC), in Petten, The Netherlands (October 2008) in
cooperation with the Institute of Energy of the Joint Research Center of
the European Commission (IE-JRC-EC), at the Royal Institute of
Technology, Stockholm (October 2009), in Petten, The Netherlands
(October 2010) in cooperation with the Institute of Energy of the Joint
Research Center of the European Commission (IE-JRC-EC) and in at
Wilmington (North Carolina, USA) in cooperation with General Electric
Hitachi, Westinghouse, AREVA NP and INL. It was recognized that such
courses represented both a source of continuing education for current
code users and a mean for current code users to enter the formal
training structure of a proposed ‘permanent’ stepwise approach to user
training. The 3D S.UN.COP 2011 at Wilmington was successfully held with
the attendance of more than 20 participants coming from more than 10
countries and 15 different institutions (universities, vendors and
national laboratories). More than 30 scientists (coming from more than
10 countries and 20 different institutions) were involved in the
organization of the seminar, presenting theoretical aspects of the
proposed methodologies and holding the training and the final
examination. A certificate (LA Code User grade) was released to
participants that successfully solved the assigned problems. The twelfth
seminar will be held (April 2012) in Daejeon, South Korea in cooperation
with the “Korea Atomic Energy Research Institute”, involving more than
30 scientists between lecturers and code developers
(http://www.nrgspg.ing.unipi.it/3dsuncop/)
BEPU current ideas
No full textRather than abstract- the Foreword is provided: A paper like the present one provides the summary of knowledge spread within the scientific community. A huge number of researchers contributed to the knowledge. BEPU activities have been performed in the last twenty years. Hereafter I wish to acknowledge (in alphabetic order) some of them who directly or indirectly have been in touch and contributed with ideas and writings to the topics discussed in this paper: N. Aksan, D. Bestion, C. Camargo, N. Debrecin, R.B. Duffey, M. Dusic, N. Fil, G. Galassi, M.R. Galetti, H. Glaeser, D. Groeneveld, Y. Hassan, K. Ivanov, P. Kirillov, L. Leung, P. Lien, O. Mazzantini, B. Mavko, F. Menzel, J. Misak, H. Nakamura, B. Nigmatulin, H. Ninokata, F. Pelayo, A. Petruzzi, R. Pochard, M. Reocreux, F. Reventos, U.S. Rohatgi, E. Sartori, R. R. Schultz and B.R. Sehgal. Many more have taught me the basics of this matter, e.g. S. Banerjee, M. Cumo, B. Guerrini, E. Hicken, H. Karwat, R. T. Lahey, F. Mayinger, K. Tasaka, F. Winkler, K. Wolfert, G. Yadigaroglu and N. Zuber. All those listed may not necessarily share the BEPU vision in the text
Consistent code qualification process and application to VVER-1000 NPP
No full textCalculation analysis by application of the system codes are performed to evaluate the NPP or
the facility behavior during a postulated transient or to evaluate the code capability. The calculation
analysis constitutes a process that involves the code itself, the data of the reference plant, the data
about the transient, the nodalization, and the user. All these elements affect one each other and
affect the results. A major issue in the use of mathematical model is constituted by the model
capability to reproduce the plant or facility behavior under steady state and transient conditions.
These aspects constitute two main checks that must be satisfied during the qualification process.
The first of them is related to the realization of a schematization of the reference plant; the second
one is related to the capability to reproduce the transient behavior.
The aim of this paper is to describe the UMAE (Uncertainty Method based on Accuracy
Extrapolation) methodology developed at University of Pisa for qualifying a nodalization and
analysing the calculated results and to perform the uncertainty evaluation of the system code by the
CIAU code (Code with the capability of Internal Assessment of Uncertainty).
The activity consists with the re-analysis of the Experiment BL-44 (SBLOCA) performed in
the LOBI facility and the analysis of a Kv-scaling calculation of the WWER-1000 NPP nodalization
taking as reference the test BL-44. Relap5/Mod3.3 has been used as thermal-hydraulic system code
and the standard procedure adopted at University of Pisa has been applied to show the capability of
the code to predict the significant aspects of the transient and to obtain a “qualified nodalization” of
the WWER-1000 through a systematic qualitative and quantitative accuracy evaluation. The
qualitative accuracy evaluation is based on the selection of Relevant Thermal-hydraulic Aspects
(RTAs) and is a prerequisite to the application of the Fast Fourier Transform Based Method
(FFTBM) which quantifies the error in code predictions related to the measured experimental
signals. A reference test scenario (SBLOCA) is then performed with the qualified WWER-1000
NPP nodalization and the CIAU code is applied for the uncertainty evaluation of the calculated
results
The ‘Code-User Effect’ and the International Training Program in Support of Safety Analysis
No full textThermal-hydraulic system computer codes are extensively used worldwide for analysis of nuclear facilities by utilities, regulatory bodies, nuclear power plant designers and vendors, nuclear fuel companies, research organizations, consulting companies, and technical support
organizations. The computer code user represents a source of uncertainty that can influence the
results of system code calculations. This influence is commonly known as the ‘user effect’ and stems from the limitations embedded in the codes as well as from the limited capability of the
analysts to use the codes. Code user training and qualification is an effective means for reducing
the variation of results caused by the application of the codes by different users. This paper
describes a systematic approach to training code users who, upon completion of the training, should be able to perform calculations making the best possible use of the capabilities of best
estimate codes. In other words, the program aims at contributing towards solving the problem of
user effect.
The 3D S.UN.COP (Scaling, Uncertainty and 3D COuPled code calculations) seminars have been organized as follow-up of the proposal to IAEA for the Permanent Training Course for
System Code Users [1]. Seven seminars have been held at University of Pisa (2003, 2004), at The Pennsylvania State University (2004), at University of Zagreb (2005), at the School of Industrial Engineering of Barcelona (January-February 2006), in Buenos Aires, Argentina
(October 2006, requested by ARN -Autoridad Regulatoria Nuclear- NA-SA -Nucleoelectrica
Argentina S.A- and CNEA -Comisión Nacional de Energía Atómica) and at Texas A&M
University (January-February 2007). It was recognized that such courses represented both a
source of continuing education for current code users and a mean for current code users to enter
the formal training structure of a proposed ‘permanent’ stepwise approach to user training.
The 3D S.UN.COP 2007 at Texas A&M. (http://dimnp.ing.unipi.it/3dsuncop/2007) was
successfully held with the attendance of 26 participants coming from 12 countries and 17 different institutions (universities, vendors, national laboratories and regulatory bodies). About
30 scientists (coming from 11 countries and 19 different institutions) were involved in the organization of the seminar, presenting theoretical aspects of the proposed methodologies and
holding the training and the final examination. A certificate was released to participants that
successfully solved the assigned problems
International Course to Support Nucklear Licensing by User Training in the Areas of Scaling, Uncertainty and 3D Thermal-Hydraulics/Neutron-Kinetics Coupled Codes: 3D S.UN.COP Seminars
No full textThermal-hydraulic system computer codes are extensively used worldwide for analysis of nuclear facilities by utilities, regulatory
bodies, nuclear power plant designers, vendors, and research organizations. The computer code user represents a source of
uncertainty that can influence the results of system code calculations. This influence is commonly known as the “user effect”
and stems from the limitations embedded in the codes as well as from the limited capability of the analysts to use the codes. Code
user training and qualification represent an effective means for reducing the variation of results caused by the application of the
codes by different users. This paper describes a systematic approach to training code users who, upon completion of the training,
should be able to perform calculations making the best possible use of the capabilities of best estimate codes. In other words, the
program aims at contributing towards solving the problem of user effect. In addition, this paper presents the organization and
the main features of the 3D S.UN.COP (scaling, uncertainty, and 3D coupled code calculations) seminars during which particular
emphasis is given to the areas of the scaling, uncertainty, and 3D coupled code analysis
The code user effect and the international training Seminar 3D SUNCOP
No full textThermal-hydraulic system computer codes are extensively used worldwide for analysis of
nuclear facilities by utilities, regulatory bodies, nuclear power plant designers and vendors,
nuclear fuel companies, research organizations, consulting companies, and technical
support organizations. The computer code user represents a source of uncertainty that can
influence the results of system code calculations. This influence is commonly known as the
‘user effect’ and stems from the limitations embedded in the codes as well as from the
limited capability of the analysts to use the codes. Code user training and qualification is an
effective means for reducing the variation of results caused by the application of the codes
by different users. This paper describes a systematic approach to training code users who,
upon completion of the training, should be able to perform calculations making the best
possible use of the capabilities of best estimate codes. In other words, the program aims at
contributing towards solving the problem of user effect. The 3D S.UN.COP (Scaling,
Uncertainty and 3D COuPled code calculations) seminars have been organized as followup
of the proposal to IAEA for the Permanent Training Course for System Code Users [1].
Eight seminars have been held at University of Pisa (two in 2004), at The Pennsylvania
State University (2004), at the University of Zagreb (2005), at the School of Industrial
Engineering of Barcelona (January-February 2006), in Buenos Aires, Argentina (October
2006), requested by Autoridad Regulatoria Nuclear (ARN), Nucleoelectrica Argentina S.A
(NA-SA) and Comisión Nacional de Energía Atómica (CNEA), at the College Station,
Texas A&M, (January-February 2007), in Hamilton and Niagara Falls, Ontario (October2007) requested by Atomic Energy Canada Limited (AECL), Canadian Nuclear Society
(CNS) and Canadian Nuclear Safety Commission (CNSC). It was recognized that such
courses represented both a source of continuing education for current code users and a
mean for current code users to enter the formal training structure of a proposed ‘permanent’
stepwise approach to user training. The 3D S.UN.COP - CANDU 2007 in Canada was
successfully held with the attendance of 33 participants coming from 8 countries and 16
different institutions (universities, vendors and national laboratories). More than 30
scientists (coming from 13 countries and 23 different institutions) were involved in the
organization of the seminar, presenting theoretical aspects of the proposed methodologies
and holding the training and the final examination. A certificate (LA Code User grade) was
released to participants that successfully solved the assigned problems. A ninth seminar is
currently holding (October 2008) at the Institute for Energy, Joint Research Centre of the
European Commission in Petten (The Netherlands), involving more than 30 scientists
between lecturers and code developers(http://dimnp.ing.unipi.it/3dsuncop/2008/index.html
International Training Program: 3D S.UN.COP-Scaling, Uncertainty and 3D Thermal-Hydraulics/Netron-Kinetics Coupled Codes Seminar
No full text- …
