Document: NUREG-0800
Document ID: 889e380e-bdb0-4af7-8056-db56551e3a1b
Document Type: srp
Title: UNCONTROLLED CONTROL ROD ASSEMBLY WITHDRAWAL FROM A
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070711.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.4.1
CFR Part: 
CFR Title: 

Content:
topical report, and frequently handled outside the scope of the review for a particular facility). c. Perform auditing-type calculations with methods available to the staff. DRAFT Rev. 3 - April 1996 15.4.1-4 d. Require additional, bounding calculations by the applicant to cover portions of the applicant's analytical methods that have not been fully reviewed or approved. 4. The input to the neutron kinetics analysis model should be examined to assure that the input is appropriately conservative both for the state of the reactor and for the particular way it is used in the analysis. The power distribution or peaking factors used in the neutron kinetics and hot pin thermal calculations must provide a conservative representation of the control rod configuration under consideration. The Doppler feedback coefficient should be related conservatively to the values accepted in the review under SRP Section 4.3, considering the time in cycle and temperature conditions of the fuel. Non-weighting of the coefficients is conservative, but weighting factors for the particular flux distribution shapes involved in the transients may be used if fully explored and justified. The moderator coefficients used should also be conservatively related to the values accepted in the review under SRP Section 4.3. The most positive or least negative values should be used and for a PWR this occurs at beginning of life . If the 12 coefficient is negative, it may be conservatively taken as zero. 5. The analysis should consider the relationships between the particular spatial flux shapes for the transient and the nuclear instrument response to assure that scrams occur at the times used in the analysis, that valid scram power levels are assumed, and that conservative scram delays and reactivity functions are used. 6. The significant results of the analysis should be presented and should include maximum power levels reached for the reactor and the peak fuel rod, reactor temperatures and pressures,