ML13031A011
| ML13031A011 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 01/11/2013 |
| From: | Carr D G AREVA NP, AREVA |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| BSEP 13-0002 51-9196989-000 | |
| Download: ML13031A011 (8) | |
Text
BSEP 13-0002 Enclosure 4 AREVA Report No. 51-9196989-000, Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)
For Information Only tý20004-019 (11/20/2012)
AREVA AREVA NP Inc.Engineering Information Record Document No.: 51 -9196989 -000 Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)Page 1 of 7 For Information Only A AR EVA 20004-019 (11/20/2012)
Document No.: 51-9196989-000 Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)Safety Related?IZYES D-NO Does this document establish design or technical requirements?
-YES I7 NO Does this document contain assumptions requiring verification?
-1 YES "] NO Does this document contain Customer Required Format? D YES Dý NO Signature Block I Name and Title/Discipline Pages/Sections PreparedlReviewed/
Approved or Comments I EE Riley, Supervisor Neutronics Richland All DG.Carr, Supervisor Thermal-Hydraulics Section 4 f AC Constantinescu, Engineer Neutronics Richland All I DR Tinkler, Engineer Thermal-Hydraulics Section 4 DE Garber, Manager Neutronics Richland All t DW Pruitt, Manager Thermal-Hydraulics All I AB Meginnis, Manager Product Licensing All Note: P/LP designates Preparer (P), Lead Preparer (LP)RJLR designates Reviewer (R), Lead Reviewer (LR)A-CRF designates Project Manager Approver of Customer Required Format (A-CRF)A designates Approver/RTM
-Verification of Reviewer Independence Page 2 For Information Only A AR EVA 20004-019 (11/20/2012)
Document No.: 51-9196989-000 Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)Record of Revision Revision Pages/Sections/
No. Paragraphs Changed Brief Description I Change Authorization 000 All This is the non-proprietary version of 51-9196691-000.
Page 3 For Information Only A AR EVA Document No.: 51-9196989-000 Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)1.0 PURPOSE This document provides supplemental information to support the USNRC review of the Reference 1 license amendment request (LAR). The referenced LAR was submitted to add SAFLIM3D to the Brunswick Unit 1 and Unit 2 Technical Specification lists of approved COLR references.
Specifically, this document addresses the impact of assemblies that are projected to exceed the fast fluence gradient basis of the existing channel bow database in the licensing basis design.
2.0 BACKGROUND
During review of the Reference 1 LAR, the USNRC has identified that some of the assemblies within an application cycle may have fast fluence gradients that exceed either the upper or lower bounds of the existing channel bow database.
The initial application cycles for SAFLIM3D at the Brunswick Nuclear Plant are expected to be Unit 1 Cycle 19 and Unit 2 Cycle 21. The licensing basis depletions for both cycles have been reviewed to determine if any assemblies exceed the existing database bounds, with the following results: Unit 1 Cycle 19: A total of six assemblies exceed the lower bound of the existing database as shown in the table below: Brunswick Unit I Cycle 19 Fast Assembly Fluence Core ID Grdent* Location Gradient*A17002 [ ] 07-44 A17003 [ ] 45-44 A17150 [ ] 09-08 A17151 [ ] 43-06 A17152 [ ] 45-10 Al 8341 [ ] 03-34 The locations of these assemblies in the Cycle 19 core are also cells in the core map provided as Figure 1.identified as the highlighted Unit 2 Cycle 21: The channel fast fluence gradients for all assemblies remain bounded by the existing channel bow database.The corresponding lower bound for the current database is C in units of 1021 n/cm 2.]. The fast fluence gradient is expressed Page 4 For Information Only A AR EVA Document No.: 51-9196989-000 Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)3.0 MARGIN TO LIMITING CPR As illustrated in Figure 1, all assemblies that were identified to exceed the fast fluence gradient bounds of the channel bow database are located in low power locations near the core periphery (i.e., located one row in from the outside of the core). This is an expected result due to the increased core leakage at the periphery which can result in increased fluence gradients.
Due to the low power in these locations, the affected assemblies will not be CPR limiting throughout cycle operation.
This is illustrated in Figure 2 in which the FLCPR (Fraction of Limiting Critical Power Ratio) for each assembly is plotted along with the core limiting MFLCPR*.4.0 IMPACT OF INCREASED UNCERTAINTY ON MCPR SAFETY LIMIT The potential impact on the SAFLIM3D calculated safety limit was conservatively evaluated by increasing the assigned uncertainty for the assemblies with calculated fast fluence gradients outside the range of the channel bow database.
The channel bow uncertainty for these assemblies was increased based on using the ratio of the channel fast fluence gradient to the nearest channel fast fluence gradient bound of the channel measurement database.MCPR safety limit calculations for Brunswick Unit 1 Cycle 19 using SAFLIM3D with the augmented channel bow uncertainty for the affected assemblies were performed on a consistent basis as analyses using the standard channel bow uncertainty.
Code inputs were used to minimize the impact of the small statistical variation from the application of Monte Carlo methods. The calculations were performed for the same MCPR safety limit values reported in the Reference 1 analyses -1.07 for the two-loop operation (TLO) analysis and 1.09 for the single-loop operation (SLO) analysis.
Comparison of the results show that the impact of applying the augmented channel bow uncertainty to the assemblies of interest was [ ] expected to experience boiling transition.
This corresponds to a change in the percentage of rods expected to experience boiling transition of [ ]. The results support the calculated TLO and SLO MCPR safety limits of 1.07 and 1.09 reported in Reference 1.Small differences in the results are expected even though the assemblies are in low power, non-limiting locations.
The power distribution in the affected assemblies and the neighboring assemblies are affected the most by the increased channel bow uncertainty.
The effect on the power distribution for assemblies further away is greatly diminished
[I.5.0 REFERENCE 1. Letter, M.J. Annacone (PGN) to USNRC, "Brunswick Steam Electric Plant Units Nos. 1 and 2 Renewed Facility Operating License Nos. DPR-71 and DPR-62 Docket Nos. 50-325 and 50-324 Request for License Amendments
-Addition of Analytical Methodology Topical Report to Technical Specification 5.6.5, "CORE OPERATING LIMITS REPORT (COLR)" and Revision to Technical Specification 2.1.1.2 Minimum Critical Power Ratio Safety Limit," BSEP 12-0031, March 2012 (NRC Accession Number ML12076A062).
The MFLCPR shown in Figure 2 is based upon the as-approved ACE correlation.
Page 5 For Information Only A AR EVA Document No.: 51-9196989-000 Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)3 11 13 15 17 19 21 23 25 52 s0 48 46 44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 A17025 A17161 A17 054 A17001 A17 083 A17235 A1714 9 A17094 A1724 3 A17125 Al17185 A17168 F-eM A17102 A18333 A17019 A18301 A17154 A18357 A19657 A18377 A18309 A19649 MM A19633 A19641 A18317 A18535 A19625 A18365 A19609 A19617 A18325 A19601 A18487 A18332 A19608 A18494 A18372 A19616 A19624 A18324 A18538 A19632 A18348 A19640 A19648 A18380 A18316 A19656 A17244 A18364 A19664 A17129 A18308 A17061 A18340 A17202 A17245 Al17211 A17 163 A17153 A18349 Al196 89 Al18539 A19665 A19823 A18455 Al19795 A18407 Al19759 Al19762 A18414 A19798 A18462 Al19826 A19672 A18477 A19696 A18356 A17 232 A17008 A17155 A18334 A18302 A19690 A18383 A18350 A19682 A19681 A19827 A19673 A18448 A18439 A19803 A19799 A18511 Al8479 A19767 A19763 A18399 A18431 A19731 A18438 A19734 A19766 A18406 A18486 A19770 A19802 A18405 A18446 A19806 A19680 A18470 A19688 A19830 Al8355 A19687 A19695 A18390 Al8339 A18307 A17140 A17237 A17126 A18 358 A19658 Al19666 A19674 A184 63 A19807 A18 503 A19771 A18471 A19735 A18423 Al18430 A19738 A18478 Al19774 A18510 Al19810 Al18502 Al19679 Al19671 Al19663 A18363 A17216 Al17167 Al18373 Al18310 Al19650 Al19831 A18440 Al19811 Al18504 A19775 A18480 A19739 A18391 A19711 A19714 A183 98 Al19742 A18454 Al19778 A18509 A19814 A18469 Al19834 A19655 A18 315 Al18376 A17212 A171'79 A17007 A18318 A18342 A19634 A18496 A196,12 A19626 A18456 A19819 A19815 A18512 A18495 A19783 A197'79 A18381 A18464 A19747 A197,13 A18447 A185:23 A19719 A19715 A18527 A18415 A19699 AJ.8422 A19702 A1971L8 A18530 A18542 A19722 A197,16 A18534 A184135 A19750 A197132 A18413 A18445 A19786 A19818 A18517 A184631 A19822 A19647 A19631 A19639 A18501 A18323 A18347 A17215 A17236 A17043 A18 366 A19610 Al19618 Al18408 Al19787 A18400 Al19751 A18392 A19723 A18531 Al19703 A18384 Al18526 Al19706 A18453 Al19726 A18518 A19754 A18389 A19790 A18397 A196 23 A19615 A18371 A17 101 Al17162 Al18326 Al19602 A18488 A19791 A18432 Al19755 Al18424 A19727 A18416 A19707 A18 519 A18472 Al19697 Al18522 A19710 Al18421 A19730 A18429 Al19758 Al18437 A19794 A184 93 A19607 A18331 A17139 27 29 31 33 35 37 39 41 43 45 47 49 51 52 50 48 46 44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 A17024 A17052 A17013 A18327 A18367 A18343 A19603 A19611 A18497 A18489 A19619 A19627 A19792 A18532 A19820 A18433 A19788 A18514 A19756 A18401 A19784 A18425 A19752 A18513 A19728 A18393 A19748 A18417 A19724 A18450 A19708 A18528 A19720 A18520 A19704 A18409 A19698 A18524 A19700 A18476 A18525 A19701 A18521 A19705 A18529 A19709 A18452 A19721 A18420 A19725 A18533 A19729 A18428 A19749 A18396 A19753 A18382 A19757 A18404 A19785 A18436 A19789 A18516 A19793 A18412 A19821 A18492 A19622 A19630 A19606 A19614 A18500 A18330 A18370 A18346 A17239 A17110 A17146 Al17186 A18319 A19635 A19643 A18457 A19816 A18465 Al19780 A18466 A19744 A18481 Al19716 A184 18 A184 19 A19717 A18541 A19745 A184 84 Al19781 A18468 A19817 A184 60 Al19646 A19638 A18 322 A17222 A17189 A18374 A18311 Al19651 Al18832 A18441 A19812 A18505 A19776 A18385 A19740 Al18394 A19712 A19713 A18395 A19741 A18451 A19777 Al18508 A19813 A18444 A19833 Al19654 A18 314 Al18375 A17 134 A17 157 A18359 A17204 A19659 A18303 A19667 A18473 A19675 A19683 A18498 A19828 A19808 A18449 A18506 A19804 A19772 A18540 A18474 A19768 A19736 A18402 A18426 A19732 A18427 A19733 A19737 A18403 A18475 A19769 A19773 A18388 A18507 A19805 A19809 A18467 A18499 A19829 A19678 A19686 A19670 A18515 A19662 A18306 A18362 A17246 A17247 Al17014 Al18335 Al19691 Al18351 Al19684 Al19676 A18442 Al19800 A18482 Al19764 A18434 A18435 Al19765 A18483 A19801 A18443 A19677 Al19685 Al18354 A19694 Al18338 Al17145 A17169 A17004 A18352 A19692 A18386 A19668 A19824 A18458 A19796 A18410 A19760 A19761 A18411 A19797 A18459 A19825 A19669 A18387 A19693 A18353 Al17203 A17 190 MEA17199 A18336 A17156 A18304 A17158 A19660 A18360 A196!;2 A18312 A196114 A19636 A19628 A18536 A19620 A19612 A18490 A19604 A18491 A19605 A19621 A19613 A19629 A18537 A1964:5 A19637 A19653 A18313 A19661 A18361 A1830.5 A17213 A18337 A17128 MHSA17233 A1721 4 A17 178 Al18378 Al18320 Al18344 Al18368 A18328 A18329 A18369 A18345 A18321 A18379 A17230 A17028 A17165 A170 59 A17166 A17 092 Al17070 A17240 A17099 A17248 A172 00 Figure I Brunswick Unit 1 Cycle 19 Reference Loading Pattern Page 6 For Information Only A AR EVA Document No.: 51-9196989-000 Supplemental Information for Brunswick SAFLIM3D Submittal:
Impact of Assemblies Outside Existing Channel Bow Fast Fluence Gradient Database (Non-Proprietary Version)W.,.J EL 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0 5000 10000 15000) 20000 Cycle Exposure (MWdIMTU)coreLimiting o A17002 A A17003 x A17150 z A17151 o A17152 e A18341 Figure 2 Brunswick Unit 1 Cycle 19 FLCPR for Assemblies outside Database Bounds Page 7