Document: NUREG-0800
Document ID: 080f80e5-ae24-4b03-bcdf-a2bdfc747da6
Document Type: srp
Title: Revision 3 - March 2007
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070790015.pdf
Revision Date: 2023-06
Chapter: 4
Section ID: 4
CFR Part: 
CFR Title: 

Content:
is power distribution control scheme can be effectively supervised with ex-core detectors. Westinghouse argues that point 3, in the CAOC methodology above (i.e., demonstrating the core conditions will not violate the envelope of permissible core power characteristics) is achieved by calculating all of the load-follow maneuvers planned for the proposed cycle and showing that the maximum power densities expected are within limits. These calculations are performed with a radial/axial synthesis method that has been shown to predict conservative power densities when compared to experimental data. While the staff has accepted CAOC on the basis of these analyses, it also requires that power distributions be measured throughout a number of representative (frequently limiting) maneuvers early in cycle life to confirm that peaking factors are no greater than predicted. Additionally, the staff is sponsoring a series of calculations at Brookhaven National Laboratory to check aspects of the Westinghouse analysis. The power distribution measurement tests described above will, of course, automatically relate in-core and ex-core detector responses and thereby validate that power distribution control can be managed with ex-core detectors. B. BRANCH TECHNICAL POSITION An applicant or licensee proposing CAOC for other than an FQ value equal to 2.32 and a bandwidth equal to ± 5 percent is expected to provide the following: 1. Analyses of FQ × power fraction showing the maximum FQ(z) at power levels up to BTP 4-1-3 Revision 3 - March 2007 100 percent and departure from nucleate boiling performance with allowed axial shapes relative to the design bases for overpower and loss of flow transients. The envelope of these analyses must be shown to be valid for all normal operating modes and anticipated reactor conditions. (See Table 1 of the letter from Westinghouse Electric Corporation to U.S. Nuclear Regulatory Commission, July 16, 1975, for the cases that must be analyzed to form such an