Document: NUREG-0800
Document ID: 63f62189-691f-402d-9ac9-41fb60ec2261
Document Type: srp
Title: DETERMINATION OF RUPTURE LOCATIONS AND DYNAMIC EFFECTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1423/ML14230A035.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.2
CFR Part: 
CFR Title: 

Content:
50-0011 and 3150-0151. PUBLIC PROTECTION NOTIFICATION The NRC may not conduct or sponsor, and a person is not required to respond to, a request for information or an information collection requirement unless the requesting document displays a currently valid OMB control number. 3.6.2-15 Draft Revision 3 – August 2015 APPENDIX A POTENTIAL NONCONSERVATISM OF ANSI/ANS 58.2 STANDARD’S JET MODELING The objectives of this appendix are to describe potential nonconservatisms in American National Standard Institute (ANSI)/American Nuclear Society (ANS) 58.2 Standard’s jet modeling (Ref. 1). It also describes how the staff performs its review of this issue for new reactor design certification applications. As stated in Section III.6 of Standard Review Plan (SRP) 3.6.2, the staff is reviewing this issue on a case by case basis. Discussion of Issues Prior to 2008, the nuclear industry commonly used the ANSI/ANS Standard 58.2-1988 for estimating jet plume geometries and impingement loads based on the fluid conditions internal and external to the piping. However, following interactions with the Advisory Committee on Reactor Safeguards (ACRS) on the jet models described in ANSI/ANS 58.2 by ACRS the staff determined that there were potential nonconservatisms in these models with respect to the (a) strength, (b) zone of influence, and (c) space and time-varying nature of the loading effects of postulated pipe ruptures on neighboring structures, systems, and components (SSCs). Blast Waves In the event of a high-pressure pipe rupture, the first significant fluid load on surrounding SSCs would be induced by a blast wave. A spherically expanding blast wave is reasonably approximated to be a short duration transient and analyzed independently of any subsequent jet formation. However, the expansion of blast waves in an enclosed space is not purely spherical, and reflections and amplifications may need to also be accounted for. Blast waves are not considered in the ANSI/ANS 58.2