Constraint-corrected fracture mechanics analysis of nozzle crotch corners in pressurized water reactors
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This paper presents fracture mechanics analysis results for various cracks located at pressurized waterreactor pressure vessel nozzle crotch corners taking into consideration constraint effect. Technicaldocuments such as the ASME B&PV Code, Sec.XI were reviewed and then a fracture mechanics analysisprocedure was proposed for structural integrity assessment of various nozzle crotch corner cracks undernormal operation conditions considering the constraint effect. Linear elastic fracture mechanics analysiswas performed by conducting finite element analysis with the proposed analysis procedure. Based on theevaluation results, elastic-plastic fracture mechanics analysis taking into account the constraint effectwas performed only for the axial surface crack of the reactor pressure vessel outlet nozzle with cladding. The fracture mechanics analysis result shows that only the axial surface crack in the reactor pressurevessel outlet nozzle has the stress intensity factor exceeding the low bound of upper-shelf fracturetoughness irrespectively of considering the constraint effect. It is confirmed that the J-integral for theaxial crack of the outlet nozzle does not exceed the ductile crack initiation toughness. Hence, it can beensured that the structural integrity of all the cracks is maintained during the normal operation.
Abstract
This paper presents fracture mechanics analysis results for various cracks located at pressurized waterreactor pressure vessel nozzle crotch corners taking into consideration constraint effect. Technicaldocuments such as the ASME B&PV Code, Sec.XI were reviewed and then a fracture mechanics analysisprocedure was proposed for structural integrity assessment of various nozzle crotch corner cracks undernormal operation conditions considering the constraint effect. Linear elastic fracture mechanics analysiswas performed by conducting finite element analysis with the proposed analysis procedure. Based on theevaluation results, elastic-plastic fracture mechanics analysis taking into account the constraint effectwas performed only for the axial surface crack of the reactor pressure vessel outlet nozzle with cladding. The fracture mechanics analysis result shows that only the axial surface crack in the reactor pressurevessel outlet nozzle has the stress intensity factor exceeding the low bound of upper-shelf fracturetoughness irrespectively of considering the constraint effect. It is confirmed that the J-integral for theaxial crack of the outlet nozzle does not exceed the ductile crack initiation toughness. Hence, it can beensured that the structural integrity of all the cracks is maintained during the normal operation.
참고문헌 (30)
- ASME B&PV Code, Section XI, Nonmandatory Appendices, Appendix G: Fracture Toughness Criteria for Protection against Failure, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (2019)
- ASME B&PV Code, Section XI, Nonmandatory Appendices, Appendix K: Assessment of Reactor Vessels with Low Upper Shelf Charpy Impact Energy Levels, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (2019)
- US NRC, "10 CFR 50.61, Fracture Toughness Requirements for Protection against Pressurized Thermal Shock Events", ~ (2006)
- US NRC, "Regulatory Guide 1.154: Format and Content of Plant-specific Pressurized Thermal Shock Safety Analysis Reports for Pressurized Water Reactors", ~ (1987)
- W. E. Pennell, "Structural integrity assessment of aging nuclear reactor pressure vessels", Nucl. Eng. Des, 172, pp.27~47 (1997)
- Fracture Analysis of Vessels-Oak Ridge FAVOR, V06.1, Computer Code: Theory and Implementation of Algorithms, Methods and Correlations, "Oak Ridge National Laboratory", Oak Ridge National Laboratory, ~ (2006)
- P. Vladislav, "Probabilistic assessment of pressurized thermal shock", Nucl. Eng. Des, 272, pp.84~91 (2013)
- Mingya Chen, "Application of the French Codes to the Pressurized Thermal Shocks Assessment", Nuclear Engineering and Technology, 48(6), pp.1423~1432 (2016), 한국원자력학회
- 최신범, "Effect of postulated crack location on the pressure-temperature limit curve of reactor pressure vessel", Nuclear Engineering and Technology, 51(6), pp.1681~1688 (2019), 한국원자력학회[DOI]
- D. Siegele, "Constraint based assessment of postulated nozzle corner cracks", Proceedings of ASME PVP (2002) PVP2002 (2002)
- S. Yin, "Stress and fracture mechanics analysis of boiling water reactor and pressurized water reactor pressure vessel nozzles", Proceedings of ASME PVP(2011)PVP2011-57014 (2011)
- F. Horokawa, "Defect tolerance assessment for ABWR nozzle crotch corner", Proceedings of ASME PVP (2016) PVP2016 (2016)
- British Energy, "Assessment of the Integrity of Structures Containing Defects. British Energy Generation Report R6 Revision, 4", Gloucester, ~ (2001)
- Welding Research Council, "PVRC Recommendations on Toughness Requirements for Ferritic Materials", ~ (1972)
- ASME B&PV Code, Section XI, Nonmandatory Appendices, Appendix A: Analysis of Flaws, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (2019)
- K. Wallin, "Irradiation damage effects on the fracture toughness transition curve shape for reactor pressure vessel steels", Int. J. Pres. Ves. Pip, 55, pp.61~79 (1993)
- ASME Boiler and Pressure Vessels Code Committee, "ASME B&PV Code, Section XI, Code Case N-629: Use of Fracture Toughness Test Data to Establish Reference Temperature for Pressure Retaining Materials", ASME, ~ (1999)
- ASME B&PV Code, Section III, Code Case N-631: Use of Fracture Toughness Test Data to Establish Reference Temperature for Pressure Retaining Materials Other than Bolting for Class 1 Vessels, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (1999)
- M. EricksonKirk, "An upper-shelf fracture toughness master curve for ferritic steels", Int. J. Pres. Ves. Pip, 83, pp.571~583 (2006)
- M. EricksonKirk, "The relationship between the transition and upper-shelf fracture toughness of ferritic steels", Fatig. Fract. Eng. Mater. Struct, 29, pp.672~684 (2006)
- M. Kirk, "Assessment of fracture toughness models for ferritic steels used in Section XI of the ASME Code relative to current data-based models", Proceedings of ASME PVP (2014)PVP2014 (2014)
- ASME B&PV Code, Section III, Code Case N-830-1: Direct Use of Fracture Toughness for Flaw Evaluation of Pressure Boundary Materials in Class 1 Ferritic Steel Components, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (2020)
- K. Wallin, "Quantifying Tstress controlled constraint by the master curve transition temperature T0", Eng. Fract. Mech, 68, pp.303~328 (2001)
- Dassault Systems, "User's manual of Simulia", ABAQUS Version 6.19, ~ (2019)
- ASME B&PV Code, Section III, Nonmandatory Appendices, Appendix G: Fracture Toughness Criteria for Protection against Failure, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (2019)
- ASME B&PV Code, Section XI, Nonmandatory Appendices, Appendix E: Evaluation of Unanticipated Operating Events, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (2019)
- ASME B&PV Code, Section II, Part D: Properties, "ASME Boiler and Pressure Vessels Code Committee", ASME, ~ (2019)
- 이경수, "원전 가압기 노즐 및 안전단 재료에 대한 기계적 물성시험 연구", 비파괴검사학회지, 33(2), pp.147~153 (2013), 한국비파괴검사학회[DOI]
- R. K. Blandford, "Tensile stress-strain results for 304L and 316L stainless steel plate at temperature", Proceedings of ASME PVP(2007)PVP2007-26096 (2007)
- E.&C. KEPCO, "Design Specification of APR 1400", ~ (2018)