Document: NUREG-0800
Document ID: b6b57a00-5b85-4f0c-965c-ca89ef4265e7
Document Type: srp
Title: DETERMINATION OF RUPTURE LOCATIONS AND DYNAMIC EFFECTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1608/ML16088A041.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.2
CFR Part: 
CFR Title: 

Content:
ing the jet dynamic loading and structural dynamic response (e.g., potential feedback amplification of blowdown forces and jet resonance effects). Each applicant was requested to explain what analysis and/or testing has been used to substantiate the jet expansion and jet loading modeling for their specific piping system design conditions and plant design configuration as described in the respective DCD. Most of the information on how other applicants addressed the concerns is proprietary. High level summaries, however, are in the DCDs and the staff’s safety evaluation reports (SERs) and may be used for guidance on future applications. Staff Review Process The following paragraphs summarize the staff’s review process for assessing the adequacy of the applicants’ dynamic jet modeling, including blast wave effects, for new reactor design certification applications. The staff assesses the applicant’s procedures to be used to analyze all loads induced on neighboring SSCs or jet shields by postulated pipe ruptures, along with the dynamic structural analyses of the SSCs. These loads include blast waves emanating from sudden pipe breaks, as well as the static and the dynamic oscillatory jet impingement forces on the SSCs and/or shields throughout the blowdown process (until all source fluid is exhausted). The staff reviews the applicant’s criteria for when and how these oscillatory loads need to be considered and determined to be conservative. For example, the staff has accepted the oscillatory jet loading to be considered for SSCs within 10 pipe diameters of two-phase jets and 25 pipe diameters of steam jets. Beyond these distances, the oscillatory jet force is negligible and therefore, does not need to be considered by the applicant. The state of a jet plume fluid often changes during a blowdown process as the pressure and temperature ratios between source and exterior fluid changes. The jet plume geometry also changes during blowdown, with a wide expansion at