UNIVERSITÀ DI PISAUNIVERSITÀ DI PISA GRUPPO DI RICERCA NUCLEARE GRUPPO DI RICERCA NUCLEARE –– SAN PIERO A GRADO (GRNSPG)SAN PIERO A GRADO (GRNSPG)
Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has
provided its prior and written consent. This document and any information it contains shall not be used for any other purpose than the one for which they were provided. Legal action may be taken against any infringer and/or
any person breaching the aforementioned obligations.
Exploitation of Exploitation of BEPUBEPU Approach for the Approach for the Licensing ProcessLicensing Process
OECD/NEA CNRA International Workshop on OECD/NEA CNRA International Workshop on
“New Reactor Siting, Licensing and Construction “New Reactor Siting, Licensing and Construction
Experience” Experience”
Hosted by the State Office for Nuclear Safety
Prague, Czech Republic
1515--17 September 2010 17 September 2010
Title Exploitation of BEPU Approach for the Licensing Process
Authors F. D’Auria, N. Muellner, D. Araneo, M. Cherubini, A. Del Nevo,
F. Moretti, C. Parisi, A. Petruzzi (GRNSPG/UNIPI – Italy)
O. Mazzantini (NA-SA, Buenos Aires – Argentina)
“with the contribution of about 40 colleagues”
Revision/Date 0 14 09 2010
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
List of content
The Atucha-2 NPP
The Licensing Framework
The Road-Map for BEPU
The BEPU Process
The Postulated Initiating Events (PIE)
The Computational Tools
The Uncertainty Method
Selected Outcomes from FSAR Chapt. 15
Conclusions
2/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
The AtuchaThe Atucha--2 NPP2 NPP 2 LOOPS 1 MCP, 1 UT SG each
1 PRZ
2160 MWth 1958 + 203 (nom. mod. T), or
2001 + 160 (max mod T)
+
14 from MCP
451 separated FC
3/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
The AtuchaThe Atucha--2 NPP2 NPP
4 Moderator loops
Moderator pump
Flow direction during
normal operation
Flow direction during
normal operation
4/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
The Licensing Framework
Conservative and best estimate methods IAEA TECDOC-1332 (01-2003)
5/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
The Licensing Framework
6/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
The Road-Map for BEPU
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
THE BEPU PROCESS - THE POSTULATED INITIATING EVENTS
83 NPP Scenarios
8/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
THE BEPU PROCESS - THE COMPUTATIONAL TOOLS
~ 20 Codes
coupling
qualification
9/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
ITF
Nodalizations
Specific
experimental data
ITF
Calculation
Accuracy
Quantification (°)
Accuracy
Extrapolation (°)
Generic
experimental
data
ASM
Calculation
a
ih
j
GI FG
gc
d
e
f
l
LN (°)
m
n
YES
FG
k
(°) Special methodology developed
Stop of the
process
NO
NO
Demonstration
of Similarity (°)
(Phenomena Analysis)
(Scaling Laws)
Code
Nodalization and
user qualification
GeneralQualification
Process
b
Uncertainty
Plant
nodalization
Plant
calculation
ITF
Nodalizations
Specific
experimental data
ITF
Calculation
Accuracy
Quantification (°)
Accuracy
Extrapolation (°)
Generic
experimental
data
ASM
Calculation
a
ih
j
GI FG
gc
d
e
f
l
LN (°)
m
n
YES
FG
k
(°) Special methodology developed
Stop of the
process
NO
NO
Demonstration
of Similarity (°)
(Phenomena Analysis)
(Scaling Laws)
Code
Nodalization and
user qualification
GeneralQualification
Process
b
Uncertainty
Plant
nodalization
Plant
calculation
THE BEPU PROCESS - THE UNCERTAINTY METHOD
THE ACCEPTABILITY
THRESHOLDS
(for the use of the uncertainty
method)
10/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
THE BEPU PROCESS - THE CASE ‘A’ AND THE CASE ‘B’
For DBA (logic diagram)
Case A (BE): All I&C considered functioning
(except PIE) serves to demonstrate the realistic
accident course – 4 redundancies working.
Case B (Conservative Case): Controls having
favorable influence are not considered. All limitation
systems are assumed to be available and a failure of
the first reactor trip system is postulated (single
failure & repair case for most effective redundancies).
Related to each Transient
11/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
The complexity of the models
Selected Outcomes from FSAR Chapt. 15
The Input DeckThe Input Deck
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Selected Outcomes from FSAR Chapt.15
TOP VIEW
SIDE VIEW
The CFDThe CFD
The boron injection in the
moderator tank
13/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Selected Outcomes from FSAR Chapt.15
The 3D NK & THThe 3D NK & TH
The Power & Flow-Rate in
each of 451 FC
14/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Selected Outcomes from FSAR Chapt.15
The Fuel AnalysisThe Fuel Analysis The The Code Coupling
15/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Selected Outcomes from FSAR Chapt.15
The Application The Application
of Uncertaintyof Uncertainty
16/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Selected Outcomes from FSAR Chapt.15
Selected FC
The Fuel AnalysisThe Fuel Analysis
The Enthalpy Release to the Fuel during LBLOCA
17/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Selected Outcomes from FSAR Chapt.15
The MechanicalThe Mechanical
LoadsLoads The Stress on RPV internal during LBLOCA
18/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Selected Outcomes from FSAR Chapt.15
The Radiological The Radiological
Impact Impact
Fuel Rupture &
Coolant Radioactivity
The Radioactivity in
Primary Circuit
The Radioactivity in
Containment
The Radioactivity in
Environment
The Doses
19/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
The ATUCHA-2 FSAR Chapt. 15 – PAPER FORMAT
20/21
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Any reproduction, alteration, transmission to any third party or publication in whole or in part of this document and/or its content is
prohibited unless the University of Pisa – San Piero a Grado Nuclear Research Group has provided its prior and written consent.
This document and any information it contains shall not be used for any other purpose than the one for which they were provided.
Legal action may be taken against any infringer and/or any person breaching the aforementioned obligations.
Exploitation of BEPU Approach for the Licensing Process
OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience” OECD/NEA CNRA Int. WS on “New Reactor Siting, Licensing and Construction Experience”
-- State Office for Nuclear Safety Prague, Czech Republic – September 15-17 , 2010
Conclusive remarks
The Atucha-2 (about 800 MWe) NPP is to be licensed by
BEPU
FSAR Chapt. 15 issued for internal review
to be transmitted to Regulatory Authority
Challenges:
simulation of control systems
use of CFD
use of 3D NK & Coupling
application of uncertainty method
Suitable Safety Margins calculated
(‘new’ computational methods applied to ‘old’ NPP
design)
21/21