ML20062N752

Nonproprietary Version of Slides from C-E/NRC/BNWL Meeting on Fates 3,Bethesda,MD 820709

ML20062N752
Person / Time
Site:	Calvert Cliffs
Issue date:	07/09/1982
From:	ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY
To:
Shared Package
ML19297F467	List: ML20062N687 ML20062N752
References
CEN-215(B)-NP, CEN-215-(B)-NP, NUDOCS 8208230330
Download: ML20062N752 (41)

Text

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CEN-215(B)-NP I

SLIDES FROM C-E/NRC/BNW  ;

l ItEETING ON FATES 3 BETHESDA, MARYLAND JULY 9,'1982 Y

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Combustion Engineering, Inc.

Uindsor, Connecticut .

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B208230330' 820817 ~'

PDR ADOCK 05000317 <

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LEGAL NOTICE THIS REPORT WAS PREPARED AS AN ACCOUNT OF WORK SPONSORED BY COlWUBTION ENGINEERING, INC. NEITHER COMBUSTION ENGINEERING NOR ANY PERSON ACTING ON ITS BEHALF:

A. MAKES ANY WARRANTY OR REPRESENTATION, EXPRESS OR llWWED INCLUDING THE WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE OR MERCHANTA81UTY, WITH RESPECT TO THE ACCURACY, COMPLETENESS, OR USEFULNESS OF THE INFORMATION CONTAINED IN THIS REPORT, OR THAT THE USE OF ANY INFORMATION, APPARATI% METHOD, OR PROCESS DISCLOSED IN THIS REPORT MAY NOT INFRINGE PZnVATELY OWNED RIGHTS;OR -

8. ASSUMES ANY UAB!UTIES WITH RESPECT TO THE USE OF,OR FOR DAMAGES RESULTING FROM THE USE OF, ANY INFORMATION, APPARATUS, METHOD OR PROCESS DISCLOSED IN THIS REPORT.

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REASONS FOR MEETINE REVIEW STATUS OF FATES 3 PRESENT NEW DATA AND ITS IMPACT ON REVIEW PRESENT C-E'S RE-EVALUATION OF SELECTED FATES 3 RESULTS BASED ON ABOVE ITEMS FOCUS ON MAIN ISSUES INVOLVING TECHNICAL MERITS OF FATES 3 RESOLVE DIFFERENCES WHERE POSSIBLE TilROUGli DISCUSSIONS ESTABLISH FRAf1EWORK FOR COMPLETING FATES 3 REVIEW

TOPICS _FJD1 BliW REVIEW 0F FATES 3 ,

1. EVALUATION OF FATES 3 BASED ON C-E DATA BASE

2. COMPARIS0N OF FATES 3 WITH A MODIFIED VERSION OF ANS 5.11 MODEL

3. EVALUATION OF FATES 3 BASED ON NRC DATA BASE 11 . EVALUATION OF GRAIN-SIZE DEPENDENCE IN FATES 3

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9 g TOPIC 1 EVALUATION OF FATES 3 BASED ON C-E DATA BASE

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DATA BASE IN C-E FATES 3 T021LAL GENERALLY PROTOTYPIC 0F Tile C-E PRODUCT LINE CHARACTERIZATION OF THE C-E RODS GENERALLY BETTER TilAN 0 tiler AVAILABLE INDUSTRY DATA e CALVERT CLIFFS I e OVER-RAMP AND SUPER-RAMP e PETTEN RAMPS e IFA-418 AND IFA-428 BELLAMY AND RICH DATA INCLUDED e HIGH INDUSTRY RECOGNITION e HIGilER BURNUP THAN C-E DATA e LARGER GRAIN SIZE THAN C-E STANDARD 0THERS (KWU, IFA-11 AND IFA-21) 1

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FISSION GAS RELEASE FROM OVER-RAMP RODS (ALL 25 DATA OVER 10 KW/FT)

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C-E RE-EVALUATION OF Tile BELLAMY AND RICH DATA NEW DATA AND DATA CLARIFICATIONS HAVE BECOME AVAILABLE REPORTED GRAIN SIZE OF FUEL WAS NOT AS-0BSERVED MLI VALUE e USE OF AS-0BSERVED VALUES APPROPRIATE IN FATES 3 e

THISCORRECTIONINCREASESGASRELEASE[ [

RICH HAS REVISED TEMPERATURE HISTORY FOR TWO HIGHEST BURNUP RODS, AND NEW FATES 3 RESULTS ARE:

e 5.6% FOR R0D 5050 AT 45 GWD/T (vs. 4.8% MEASURED) e 5.8% FOR R0D 5049 AT 48 GWD/T.(vs. 7.8% MEASURED) .

FATES 3 PROVIDES A GOOD OVERAlL PREDICTION OF THE 17 BELLAMY AND RICH RODS, INCLUDING 5 RODS IN THE RANGE OF 30-48 GWD/T THE RANGE IN BURNUP (8-48 GWD/T) AND THE RANGE IN FUEL CENTRAL TEMPERATURES (850-1650 C) INCLUDED IN THESE DATA SUPPORT THE SEPARATION OF THERMAL AND BURNUP EFFECTS IN FATES 3

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9 0 8 9 TOPIC 2 FATES 3 COMPARISON WITil REVIEW MODELS vW e

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FATES 3 COMPARISDH_HLIll REVIEW _110DELS. -

BNW COMPARIS0N OF FATES 3 WITil MODIFIED ANS 5.11 MODEL WAS DONE -

FOR IS0TilERMAL CASE (GRAIN GROWTH AT BOL)

NRC COMPARIS0N OF FATES 3 WITil MODIFIED ANS 5.11 MODEL, AND BEYER-HANN + NRC CORRECTION MODEL, WAS DONE WITil GRAIN GROWTil RESTRAINT ATHIRDCASEISADDED[

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THE TilREE CASES CONSIDERED ARE REPRESENTATIVE OF TIIE SPECTRUM 0F FISSION GAS RELEASE PREDICTED DY FATES 3 FOR WIDELY VARYING R0D POWER llISTORIES ,

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C-E CONCLUSIDHS ON MODELS C011PARISDN

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POWER HISTORY IS AN IMPORTANT CONSIDERATION IN Tile COMPARISON OF MODELS W!1ICll ACCOUNT FOR MORE TilAN IS0TilERMAL RELEASE MECilANISMS. Tills IS RE-FLECTED IN THE GOOD COMPARIS0N OF FATES 3 WITH Tile CEN-1G1 DATA.

Tile POWER RAMP HISTORY PROVIDES SIGNIFICANTLY MORE FISSION GAS RELEASE THAN DOES Tile IS0TilERMAL HISTORY A. VENDOR MODEL ULTIMATELY Sil00LD BE EVALUATED ON DATA COMPARISONS WilICil INCLUDE Tile !.IMITING OPERATING HISTORIES REPRESENTATIVE OF ANTICIPATED OPERATIONAL TRANSIENTS

-- RAMP TESTS LIKE THOSE AT STUDSVIK AND PETTEN ARE REPRESENTATIVE OF THESE LIMITING OPERATING llISTORIES

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THE NRC DATA BASE MOST RODS (11 0F 12) ARE UNPRESSURIZED

- -SOME RODS INCLUDED NON-TYPICAL, AS-FABRICATED FUEL STRUCTURES SOME RODS EXPERIENCED EXTENSIVE COLUMNAR GRAIN REGIONS AND LARGE CENTRAL VOIDS THE ONLY PRESSURIZED R0D IS A BLIND R0D FROM A LARGER DATA BASE i

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CDEARISDN OF DAIA_ BASES

_NRC_DAIa_ BASE __

TOTAL NUMBER OF RODS 12 LHGRS > 10 KW/FT 12 BU > 30 MWD /KGU 4 PEAK LHGRS (KW/FT) 13.7 - 17.8 PEAK BURNUPS (MWD /KGU) 19 - 53 GRAlil SIZES (pM) ** 5 - 25 DESIGN PRESSURIZED 1 NON-PRESSURIZED 11 INCLUDES 8 RODS FOR WilICil FISSION GAS RELEASE DATA WERE PROVIDED IN RESPONCES TO NRC QUESTIONS AS-0BSERVED, MEAN-LINEAR-INTERCEPT VALUES

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BNW EVALUATION OF FATES 3 FOR

_IllE_NRC DATA BASE - IFA-432 RESULTS BNW HAS Cll0SEN TO EVALUATE RODS 1-4 BASED ON THE CENTRAL GRAIN SIZE DESPITE OBVIOUS CRYSTALLIllE DEFECTS IN Tile FUEL BNW HAS RECOGNIZED THE CONSERVATISM IN Tile C-E DENSIFICATION MODEL FOR DENSIFYING FUEL IN R0D 6 BNW IS CONCERNED TilAT THERMAL FEEDBACK IS MODELED INCORRECTLY BASED ON THE READING 0F ONE THERM 0 COUPLE O

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REF: NUREG/CR-0332 f- (BNWL-1988, R3)

NOVEMBER 1977

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CEN-193(B)-P SUPPLEllENT 2-flP REF:

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! Fig. CA-2. Comparison of Heasured and FAi[53 Predicted Centerline fuel Temperatures for the Lower IC '

Locations in Rods 1 and 4 of IFA-432 (95110 5 table. 9 mil 9aP) l l

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limansE. E M Measured Predicted. 22 ,m Fuel Grain $lae

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(lle fill Standard) 6 3 18 8 fleasured O Predicted. 22 ,m fuel srain $1:e

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SEP MC pl4hCN JUNE SEP KC MARCN JUNE KC MARCN JUNE SEP SEC ManCN JtstE '79 '80 '80 MC MARCN JUNE SEP

'78 '78 '7s '78 '79 '79 '79

'75 '76 '76 '76 '76 '77 '77 , '77 '77 ilHE E

REF: CEN-193(B)-P SUPPLEMENT 2-NP Fig. LA-E Comparison of Measured and FATES 3 Predicted Centerline fuel Temperatures for the Upper and Lower 10 Locations in Rod C sf IFA-432 (921 IDUnstable,9milgap)

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I C-E RE-EVALUATION OF FATES 3 FOR IEA '132.

USE OF AS-0BSERVED MLI GRAIN SIZES IUCREASES GAS RELEASE, INTERNAL PRESSURE, AND FUEL TEMPERATURE FOR ALL RODS DUE TO GRAIN DEFECTS IN FUEL OR RODS 111, AN APPROPRIATE EVALUATION WOULD BE BASED ON ~ 22 p H l -

BASED ON THESE FACTORS, FATES 3 PROVIDES OVERPREDICTIONS OF GAS RELEASE i

EXPECTED FOR ALL RODS -

- ;CONSERVATISMS IN THE FATES 3 BOL GAP CONDUCTANCE CALCULATION, ESPECIALLY IN THE FUEL DENSIFICATION MODEL, PROVIDES A CONSERVAIIVE PREDICTION OF

Tile THERMAL FEEDBACK EFFECT BEFORE IT OCCURS FUEL R0D H0T PRESSURES APPEAR TO BE OVERPREDICTED TO A GREATER DEGREE THAN IS GAS RELEASE THESE NEW RESULTS SUPPORT THE GRAIN SIZE DEPENDENCE IN FATES 3

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C-E EVALUATION OF FATES 3 FOR Tile NRC DATAJASE - RISO RODS C-E STILL MAINTAINS THAT ROSS-ST0UTE DATA ON FABRICATION ROUGilNESS EFFECTS ARE INAPPROPRIATE AT HIGil BURNUPS UNCERTAINTIES ARE PRESENT IN THE AS-FABRICATED GRAIN SIZE OF RISO FUEL FISSION GAS RELEASE. AND MICR0 STRUCTURAL FEATURES OF RISO RAMP RODS DIFFER LITTLE FROM THOSE OF Tile IIIGli BURNUP RODS, YET TilEIR POWERS AND FUEL TEMPERATURES WERE SIGNIFICANTLY LOWER, ESPECIALLY AFTER 5 GWD/T RISO RAMP R0D RESULTS (BWR AND PWR RODS) DIFFER SIGNIFICANTLY FROM Tile BULK 0F THE INDUSTRY UO2 RAMP TEST DATA, AND Tile REASONS REMAIN SPECULATIVE AT LTHIS TIME m

REF: CEN-193(B)-P SUPPLEMENT 2-NP A Comparison of FATES 3 Predictions and

Measured Values of Fission Gas Release for Five Nonpressurized RISd Test Rods i HIGHBURJUPRODS RAMPED RODS 4

Test Series 022 022 ,

013, 050 013, 055, 067 013, 055, 067 Rod Identity PA29-4 M2-2C [ M20-1B M2-28 .T9-3B Diametral Gap, mils 9.4 9.4 8.3 8.7 9.4

$ Wt. Fraction of Fuel in $

End Pellets 0.14 0.16  ; 0.21 0.21 0.21

Fuel

Wt.% U-235  :

Center Pellets 2.28 2.28 -

1.45 1.45 1.45 End Pellets 0.72 0.72 0.72 0.72 0.72 T .

% Fuel Grain Size, um -

Center Pellets 8 8 25 25 25 End Pellets 15 15 15 15 15 Lifetime-Peak. Rod-Averaged $

Power,kw/ft 17.8 16.8 16.1 14.4 14.9 EOL Rod-Averaged  :

Burnup, GWd/MTU 45.4 43.1 -

29.9 28.7 30.4 Measured Fission Gas .

R31 ease, % 48.1 35.6 38.9 29.5 29.6 FATES 3 Predicted Release, % 35.2 30.5 9.4 5.3 7.7 FATES 3 Predicted Release for 44.9 40.2 -

12.3 7.2 10.2 Commercial Fyel Surface .

Roughness. % .

-5

" Reported roughnesses are in the range of 4-6x10 , in (RMS) for the RISS fuel pellets,

Commercial fuel roughnesses are typically about 8x10-5 in(RMS).

REF: CEN-193(B)-P SUPPLEMENT 2-NP Relative Differences in Powers and Predicted fuel Centerline Temperatures Among the RISS Rods Early Peak Differences

• Late Peak Differences h (at 2-4 Mwd /kgu) (at 28-30 Mwd /kqu) '

Test Rod c c Series , Identity Localkw[ft AFk Local kw/ft AFk 022 PA29-4 18.7 0 (base) 17.9 0 (base) k 111Gll BURNUP

.. 022 , , , , , , y,-2C,,,, , ,,, ,,17,.7 , ,, , , ,260 ,,,,,,,,,,, 17.0 ,,, , ,-240, . . . - RODS

, 013, 050 M20-1B 16.9 -360 13.7 -1070 013,055 067 H2-2B 15.1 -670 12.7 -1410 i RAMPED RODS 013, 055 T9-38 15.8 -460 13.4 -1200 a

, 067 de m

"At axial center of each rod. For the 022 Test III. For the.013TestSeries,thiswasperiodnumber121b.les,thiswasperiodnumber130 b

At axial center of each rod. Fo h III. For the 050 Test Series, this was period 169 2 .e 022 Test ForSeries, the 067this was Test periodthis Series, 158was period 180.

C FATES 3 relative predictions of fuel centerline temperatures at approximately the axial center of each rod.

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BNW EVALUATION OF (BLIND) RJL R0D BNW STATES THAT THIS R0D EXPERIENCED MODERATE FUEL CENTRAL TEMPERATURES 0000 - 1250 C) THROUGHOUT ITS IRRADIATION (BASIS? DENSIF ,tlG FUEL TEMPERATURES WOULD HAVE BEEN GREATER)

BNW IS SURPRISED THAT E0L GAS RELEASE PREDICTED BY FATES 3 IS LOWEST WHEN DENSIFICATION IS HIGilEST (LONG TERM EFFECT OF DIFFERENT FUEL CONDUCTIVITIES ARE IMPORTANT)

BNW STATES THAT THE FATES 3 PREDICTIONS FOR VARIOUS DENSIFICATION ASSUMPTIONS WERE ALL LOWER THAN MEASURED (HOW MUCH LOWER?)

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e LONGER DIFFUSION DISTANCE IN LARGER GRAINS

, o GRAIN GROWTH KINETICS DEPENDS ON GRAIN SIZE AS-0BSERVED l1LI GRAIN SIZE VALUES Sil0ULD BE USED IN FATES 3, CONSISTENT WITH THE DEVELOPflENT OF Tile MODEL AND ITS INTENDED APPLICATION 1

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, C-E CONCLllSIDHS IRRADIATION llISTORY IS AN IMPORTANT VARIABLE. CONSIDERED BY Tile C-E MODEL, AS WE BELIEVE IT IS FOR REAL FUEL RODS THE POWER RAMP HISTORY APPEARS TO BE THE LIMITING llISTORY FOR CURRENT LWR DESIGN FUEL RODS FOR THE CALCULATION OF FISSION GAS RELEASE AND R0D INTERNAL PRESSURE THE C-E DATA BASE INCLUDES SIGNIFICANT RAMP TEST DATA WHICil SUPPORT FATES 3. THESE DATA WILL BE ENHANCED WITil DATA AB0VE 110 GWD/T IN LATE 1982 1

LARGE GRAIN FUEL PROVIDES A VIABLE METHOD FOR REDUCING RELEASED FISSION GAS AND,.THEREFORE, ITS USE SHOULD NOT BE DISCOURAGED

" - SIGNIFICANT DATA EXIST IN THE FATES 3 TOPICAL TO EVALUATE FATES 3 AB0VE

, s 10 KW/FT AND BEYOND 30 GWD/T s

BASED ON THESE DATA,.AND THE C-E RE-EVALUATION OF THE NRC DATA, FATES 3 APPEARS APPROPRIATE AT LINEAR POWERS GREATER THAN 10 KW/FT AND BEYOND 30 GWD/T. AT Tills _ POINT C-E BELIEVES FATES 3 TO PROVIDE OVER-ALL FISSION GAS RELEASE PREDICTIONS BEYOND 30 GWD/T THAT ARE BEST ESTIMATE TO AT j LEAST 50 GWD/T.

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