ML19327B016

Cycle 7 LOCA Limits.

ML19327B016
Person / Time
Site:	Davis Besse
Issue date:	10/11/1989
From:	Anderson G, Rinckel M BABCOCK & WILCOX CO.
To:
Shared Package
ML19327B014	List: ML19327B013 ML19327B016
References
86-1176204-01, 86-1176204-1, NUDOCS 8910240193
Download: ML19327B016 (63)

Text

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ATTACHMENT it- 'BABC0CK & VILCOX REPORT NUMBER 86-1176204-01 DB-1 CYCLE 7 LOCA LIMITS I.

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PDR ADOCK 05000346 D_.__________ _ ____f!R3L _ _______ --.

s; a- BWNP 206971 (6/88)

" CALCULATION

SUMMARY

SHEET (CSS) ooCUMENT IDENT!FIER 86-1176204-01  :

TITLE DB-1 Cycle 7 LOCA Limits PREPARED BY: REVIEWED BY:

NAME M.A. Rinckel nAug G.E, Anderson SIGNATURE M SIGNATURE I rittg Engineer IV OATE TITLE Principal Engineer 9,7g /4/ h /Pt COST CENTER REF. PAGE(S)

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TM STATEMENT: REVIEWER INDEPENDENCE b .

PURPOSE AND

SUMMARY

OF RESULTS: ,

Purpose:

To calculate Cycle 7 LOCA Limits for DB-1 which include NUREG-0630, TACO 2 MK-88A fuel data (including a revision of the CEF correlation, from BAW-2 to BWC),

FLECSET reflooding heat transfer coefficients, and revised ECCS injection parameters.

Results: The Revised LOCA limits calculated in this anlaysis, the Cycle 6 (Interim LOCA Limits), and the BAW-10105, Rev.1 LOCA limits are provided below. .

Elev. (ft) Revised LOCA Limit Interim (1987) BAW-10105 (1975) 2 16.00 kw/ft 15.5 kw/ft 16.5 kw/ft 4 15.75 kw/ft 16.8 kw/ft 17.2 kw/ft 6 16.50 kw/ft 17.0 kw/ft 18.4 kw/ft 8 17.25 kw/ft 17.5 kw/ft 17.5 kw/ft 10 17.00 kw/ft 17.0 kw/ft 17.0 kw/ft The increase in the 2 ft LHR was attributed to the use of the FLECSET reflooding L

u HTC code. The reduction in the 4 ft LHR was attributed to a combination of the BUC CHF correlation and the FLECSET HTC code. The reduction in the 6 ft LHR was attributed to FLECSET, and the reduction in the 8 ft LHR was attributed to the ,

BWC correlation.

l Note: The ournose of this document is to correct miscellaneous errors found in Rev. O.

(i.e., gpta,zA>6 of Ett'CAC4 A6 AIELL A$ Retots ZAJ 746t.t$ V2r/

ANA 4/A/- /). E'6/. O/ JOAEW44E6 R&, oc.

THE FoLLoWING COMPUTER CODES HAVE BEEN USED IN THIS DOCUMENT:

CODE / VERSION / REV THIS DOCUMENT CoNTAINS i CODE / VERSION / REV ASSUMPTloNS THAT MUST BE

(- VERIFIED prior To USE i

N/A ON SAFETY RELATED WORK YES ( ) No( X)

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'IABIE OF 00tfffNTS 1

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1. Ilf1HXIJCTICH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.. CWC2DS ICH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 ,

3. ME'IHOD OF At& LYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4. RESULTS OF ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 ,

4 .1. 2 FT ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

.i 4 . 2 . 4 FT ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 P

4 . 3. 6 PT ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 4.4. 8 FT ANALYSIS................................... 47 4.5. 10 FT ANALYSIS ................................. 54 t

4.6 ADDITICEAL WHOIE CORE ME'IAL WATER REACTICW. . . . . . 57

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4.7 Cycle 6 IDCA Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 1

5. REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 i,

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1. DmOpUCTION j l

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During a postulated loss-of-ooolant accident (IDCA), when the reactor coolant I pressure drops below the fuel rod internal pressure, the fuel claddirg may swell ard rupture for particular ocubinations of strain, fuel rod internal pressure, cladding tenparature, and material properties of the claddirg.

Reactor thermal and hydrodynamic behavior durirq a LOCA are dependent upon the type of accident, the time at which swelling and rupture occur, and the resultant coolant flew blockage.

Appendix K of 10 CFR 50.46 requires that the cladding swelling and npture  ;

calculations be haami on applicable data in such a way that the degree of swelling and incidence of rupture are not urderestimated. In order to establish an industry data base, the NRC has sponsored several rammarch p%num on ,

cladding behavior during ard after a IDCA. NUREG-06301 is haami on this research. NUREG-0630 contains revised models for cladding rupture, strain, and blockage during ard following a IDCA whim differ frcan the accepted B&W evaluation nodal (BAW-10105, Rev. 12 ),

Eacn utility with a B&W designed NSSS was Inquired to provide the NRC with supplemental large Break Ioss of Coolant Accident (IBIDCA) calculations l

l ammaaning the inpact of NUREG-0630. In accordance with the NRC request, 'Ibledo FAiarri (TE), whi& operates a B&W raised-loop 177-fuel assembly (FA) plait, submitted IOCA calculations at the 2 ard 6 ft oore elevations 3e4. Following the i

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86-1176204-01 6 submittal and subsequent review of. the 2 and 6 ft analyses, the NRC requested additional ammaammants for the 4, 8, and 10 ft elevations. '1he analyses at the 5

4, 8, and 10 ft elevations have been ocupleted and are included in this report.

t Charryes to the Davis naama fuel design have also affected the IOCA evaluation i model. 'IE is currently approaching the end of their current fuel cycle, cycle .

6, and will be introducing MK-B8A fuel in Cycle 7. MK-B8A fuel differs frun the MK-B5 annanblies currently in the core in that . the MK-BBA fuel assembly includes a< lower pin pre-pressure. . '1ha MK-BBA assembly also includes zirraloy i spacer grids,.whereas the MK-B5 assembly contains spacer grids constructed from inoonel. '1he use of zircaloy spacer grids in B&W fuel assemblies has historically required a change in the critical heat flux (OF) correlation  !

(frun the BAW-2 correlation to the IWC correlation) used for fuel design S and .

IBLOCA calculations6 ,7,8. When ocupared to the BAW-2 OF correlation, the EHC correlation has been shown to be more accurate with respect to OF testing of the MK-BBA type fuel assembly, and also more limiting in terms of IBIDCA calculations (i.e., lower IOCA limits 6),

l Another evaluation nruial change incorporated the use of the FIECSET reflooding heat transfer coefficient (NIC) code. '1ha FIECSET code was approved for use in the B&W IBIOCA Evaluation Model (EN) in October of 1987, as reported in BAW-1915A 9 . '1he BAW-1915A evaluation included a M=== ion of the inpact of the FIECSET10 reflooding heat transfer coefficients on the 177 FA lowered-loop operatirmJ IOCA limits, the results of which are suranarized as follows: FIECSET resulted in a .5 kw/fc increase at the 2 ft elevation, and no benefit or 4

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86-1176204-01 penalty at the 4 through 10 ft elevations. The FIECSFP code was iglemented for  ;

tho' analyses reported herein, thus replacing the FIECKAll and M 2 codes used for all previous n Ialoca evaluations. '

- A fourth m modification included the followisq twvision of ECCS injection ,

paramatars: TE has requested that BfM include an additional 5 somnd ECCS-injectics) system delay in order to provide additional margin for actuation of their motor driven ETS systans. In addition, 2 has requestad that BW  ;

implanant CPT initial conditions whicts reflect the lowest allowable pressure and inventory per TE 'Dactinical Specifications (75) .

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! In ordsr to establish IDCA limits which incorporata NUREG-0630, the MK-B8A fuel, the recently approved FIECSEP reflood heat transfer coefficients, and the variation in EoCS ancillary system assunptions, IBIOCA analyses were performed for the 177 FA raised-loop plant at eacts of the 2, 4, 6, 8, and 10 ft elevations. 'Ihe analyses were performed utilizing the follcwi29 IDCA *:

CRAFT 213, REFloD314, FIECSEra and 'INEIAl-B15 Initial fuel and cladding l

i dimensions, and fuel tasperatures, which are required inputs for the GAFr2 and

'INEIAl-B simulations, wers obtained frun the TA002 16 fuel model.

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e 86-1176204-01 I 2. OCNCIUSIONS

,, An ECCS boundirg analysis was performed to datamine the operating IDCA limits for the B&W 177-fuel aseenbly (FA) raised-loop plant. 'Ihe followirg Di related  ;

modifications were incorporated in this analysis NURm-0630 cladding rupture '

data, TACD2 MK-BBA fuel aseenbly data (including a zwvision of the CEF correlation from BAW-2 to IMC) , the FIECSET refloodirq heat transfer b ocefficient corzulation, and the variation of ECCS parameters (i.e., LPI/HPI delay and initial CFT prussure and inventory). 'Ihe break analyzed was an 8.55-ft2 double-ended cold leg rupture at the RC pung discharge with a discharge coefficient of 1.0. 'Ihe IDCA limits wars calculated at each of the 2, 4, 6, 8, ard 10 ft elevations.

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'Ihe Beginning of Life (BOL) IOCA limits established L. uds analysis, the interim IDCA limits established for Cycle 6, and the original BAW-10105, Rev.

1, IDCA limits are presented in Table 2-1. 'Ihe interim IOCA limits were established in Septater of 19871~ ard contained analyses at the 2 and 6 ft i elevations which incorporated the following Di model modifications: TACD2 fuel data, NUREG-0630 cladding rupture data, and FIECl% reflood heat transfer coefficients. 'Iha interim IOCA limits at the 4, 8, and 10 ft elevations were established by reducing the BAW-10105, Rev.1, IOCA limits in accordance with the 177 FA lowered-loop penalties due to 'IACD2 ard NURM-06303*4 A revised IOCA limit of 16.0 kw/ft was calculated at the 2 ft elevation. 'Ihe Linear Heat Rate (IER) of 16.0 kW/ft represents a 0.5 kw/ft increase with 6

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I 86-1176204-01 ress a t.o the prwvious 2 ft interim IOCA limit 3. Se increase in the 2 ft LOCA limit as attrikuted to the use of FIECSET reflooding heat transfer coefflu *1ts. No inpact was attributed to the use of the BWC OF oorrelation. i me tida at whis 12iB was h ived in the hot channel did not change i

significantly when ocupared to a similar 2 ft analysis in which the BAW-2 QF .

correlation was used. Se revised ECCS injection paramatars did not result in a

. reduction in core reflooding capacity because the ECCS injection pumps were -

actuated before the CFT's enptied.

he IDCA limit at the 4 ft elevation was calculated to be 15.75 kw/ft, a 1.45  ;

kW/ft reduction with r+-t to the BAW-10105, Rev.1, limit, and a 1.05 kW/ft ,

reduction with respect to the interim IDCA limit. Se 15.75 kw/ft limit ,

resulted in a peak clad tanparature of 2049.46 F in the ruptured node at 40.77 seconds. No inpact was estimated due to the implementation of MK-B8A TACO 2 fuel data, or the revised ECX:S injection parameters. However, the use of the IMC OF oorrelation arx1 the FIECSET reflood heat transfar coefficients both contributed to the reduction in the 4 ft um.

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l 2e BWC OF oorrelation resultad in an earlier inception of INB at the 4 ft

[ elevation than the BAW-2 CHF oorrelation in both the CRAFr2 arx1 'IHEIAl-B simulaticris. m is earlier prediction of INB resultad in additional stormd energy in the fuel at the erd of adiabatic heatup (ILAH). In order to quantify the impact of the IMC correlation the 4 ft calculation was repeated with the BWC OF correlation replaced by the BAW-2 CHF oorrelation in both the CRAFr2 l- ard 'IHEIAl-B sinulations. A linear heat rata of 16.25 kw/ft resulted in a l

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86-1176204-01 ryptuzid nodo peak c.1,ad tanperature of 1767 F (9 40 seconds) and an unruptured node peak clad tamparature of 1951 ~ F. (9 85 second) . Since the 4 ft analysis became unruptured node limited, and also exhibited considerable margin to the  ;

allowable Peak Clad Tenparature (PCT) limit of 2200 F, it is estimated that the allowable IJIR could have been increased by an additional 0.5 kw/ft. The impact of the BWC O!F correlation at the 4 ft elevation was established at 0.5 kW/ft and may have been as ax:h as 1.0 kw/ft.

i The FIECSEr reflooding heat transfer coefficients at' the 4 ft elevation were substantially lower than the 4 ft FIECKA heat transfer coefficents implemented in the 4 ft base case analysis 1 at the time at whidt the PCP was observed in 1 the ruptured node. The use of FIECSEr may have resulted in a penalty at the 4 t

ft elevation. The inpact of NUREU-0630 was estimated to be 0.4 kW/ft, as ,

established in Ref. 3.

1 In sunnary, the reduction of the 4 ft IDCA limit to 15.75 kw/ft, fran the 5

interim IDCA limit of 16.8 kw/ft, has been attributed to a conbination of the use of the BWC O(F correlation as well as the FIECSEP reflood heat transfer ocefficient code.

A linear heat rata of 16.5 kw/ft was calculated for the 6 ft elevation. This ,

rupe *. 0.5 kW/ft reduction with respect to the 6 ft interim IDCA limit3 .

The 0.5 L/f t reduction was attributed to the use of the FIECSEP reflooding heat transfer coefficient code. The previously used FIECKA code provided substantially higher heat transfer coefficients over the interval in which the 8

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86-1176204-01 peak clad temperature was r*= awed in this analysis. No inact was estimated for the IMC OF correlation since the time at whid [NB occurred .in the hot  !

channel did not change frtza the earlier analysis in which BAW-2 was iglemented. No igact due to the revision ja ECOS injection parameters was estimated for the same reasoning as described in the 2 ft section above.

A linear heat rate of 17.25 kw/ft was obtained at the 8 ft elevation. 'Ihis Igrements a 0.25 kw/ft reduction frtza the BAW-10105, Rev. 1, limit. 'Ihe F

reduction was attributed to the BWC OF correlation, which predicted an earlier cocurence of ENB for the 8 ft case. No igact due to either TA002 or NUREG-0630 ,

was realized as the peak clad temperature was observed in the unruptured node.

i No inpact due to the use of the FIEc5Er correlation was estimated. No igact due to the revised ECCS ancillary system parameters was realized since the core flooding rates were equivalent to the preceding flooding rates inplemented for l

the BAW-10105, Rev. 1, analysis.

'Ihe revised IDCA limit at the 10 ft elevation was 17.0 kw/ft, which is identical to the BAW-10105, Rev.1 limit, and the interim IDCA limit. None of L

L the EM modifications impacted the 10 ft IDCA limit.

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l A sumary of the current IOCA limits, includinJ the evolution with re-p-t to the BnW-10105, Rev.1, IOCA limits, in presented in Table 2-2. It should be l; noted that the individual anaammnant of each inpact was obtained qualitatively; 1

l' in end instance more than one EM modification was implenented in parallel.

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'Ihe addition of zircaloy spacer grids to the Davis naama core, via the MK-B8A fuel assembly, required a ruovaluation of the whole corn metal water reaction l

followirq a IRIDCA. 'Ihe App. K 10 CFR 50.46 rule for whole core metal water . -

reaction states that the amount of hSm. generated fran the chenical reaction of the claddirq with water or steam shall not exceed 0.01 times the hypothetical amount that would be generated if all of the metal in the claMigg cylinders surrounding the fuel, excludirg the cla&iirq surrounding the plenum volume, were to react. Since acume of the zircaloy grids will contribute to the overall h%+ generation, an assesment of the additional whole oors metal water reaction due to the presenom of zircaloy grids was performed. 'Ihe whole core metal water reaction was estimated to increase by 0.17 % with respect to the 0.53% value reported in section 9 of BAW-10105, Rev.1. 'Ihe revised whole

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core metal water reaction was therefore estimated at 0.70%, well below the 1% i limit specified in 10 CFR 50.46.

'Ihe reductions in the revised allowable linear heat rates at the 4, 6, and 8 ft elevations with rear =t to the interim IDCA limits (Table 2-1) inplemented for *

. Cycle 6 operation were investigated due to the potential safety concern. It was +

oencluded that the reductions at the 4, 6, and 8 ft elevations were attributed to the use of the IMC GF correlation and/or the FIECSET reflooding heat transfer coefficient correlation. Both of these nodel changes are applicable to Cycle 7 operation; therefore, the use of the interim IDCA Idmits for Cycle 6 operation was acceptable, and did not constitute a safety concern.

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TAIEE 2-1 SUM 4ARY OF IDCA LDGTS F

EIEVATIM (PT) REVISED IDCA LDGT DTI'ERIM IDCA LDGT BAW-10105 r 2 16.0 W/FT 15.5 W/FT .16.5 W/FT 4 15.75 " 16.8* " 17.2 "

6 16.50 "- 17.0 18.4 " i 17.5* " 17.5 "

8 17.25 "

17.0* " 17.0 "

10 17.00 "

• Represent IOCA limits which were estimated haami upon the inpact of NUREG- r 0630 and TACO 2 on the 177 FA lowered-loop 4, 8, and-10 ft elevations.

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TABIZ 2-2 (

IDCA LIMrIS - El!rrIMATED EVOI17FIQ4 W/ RESPECT 'ID BAW-10105 2 FT 4 FT 6 FT 8 FT 10 FT (IM/FT) (10f/FT) (IM/FT) (M/PT) (W/FT) s BAW-10105 16.5 17.2 18.4 17.5 17.0 TACO 2 -0.5 0.0 0.0 0.0 0.0 IfJREG-0630 -0.5' ~ -0.4 -1.4 0.0 0.O ECCS lODIP'ICATIONS 0.0 0.0 0.0 0.0 0.0 INC CORRE2ATICH -0.0 0.0 .25 0.0 CDS. FIEOSET/BWC -1.05 FIECSET +0.5 .5 0.0 0.0

'IUIAL 16.0 15.75 16.50 17.25 17.0 -

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86-1176204-01 3.0 MEIHOD OF ANALYSIS We analytical methods used in this study are the same as those dam ibed in

- the BW EOS evaluation model topicals, BW-10104, Rev. 518, and BW-10105, '

Rev.1, except for the modifications due to NUREC-0630 3, MK-BBA fuel 19, and the FIECSEP reflood heat transfer coefficient oorzulation. In addition TE has requestad modifications to the IPI,. HPI, and CFF EOCS systens with respect to ,

delay, flow capacity, and initial inventory (CFr). Se break analyzed was an 8.55-ft2 double-ended cold leg rupture at the - RC pung discharge with a discharge coefficient of 1.0. Se Evaluation Model (D() modifications are diar w aad in detail below. ,

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l 3.1 IODIFICATIONS DUE 'IO NURED-0630 ,

'Ihe overall effects of NUREG-0630 incle the followim ,

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1.. Se NURED-0630 rupture tanparature as a function of engineering hoop stress correlation with a heating rang of 0 C/s, shown in Figure 3-1, was used. Bis rang rate represents a boundirq value for rupture data as  ;

established in references 2 and 3.

j. 2. Se NUREG-0630 strain versus tanparature data are contained within a fast and slow rang rate correlation. Se circumferential strain model, Figure L 3-2, used in this analysis bourds the ocuposite of the fast ard the slow l

models.

3. 'Ihe NUREG-0630 coolant flow blockage data, Figure 3-3, is derived from i

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86-1176204-01 l burst strain data, whi& bounds the ocuposite of the alw and fast raup

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The above effects are incorporated into specific analysis models as follows.

2he CRAFT 2 model includes stress versus ruptuce temperature data and channel blockage as a function of the reduction in f1w area data; input charges to the q THL'Ihl-B code include stress versus taperat21re data and mav M nn red circumferential strain data. These changes fu ly inplement the NURB3-0630 required i.W 2anges.

3.2 PODIFICATIGIS IKE TO MK-B8A FUEL:

The Davis Besse Cycle 7 reload, which in scheduled for early 1990, will include a transition core with approximately 1/3 of the core containing fresh MK-B8A fuel assenblies, and the remaining 2/3 core containing once and twice burned  :

MK-B5 fuel assenblies. The psW intn: duction of MK-BBA fuel into the TE core has required then investigation of the following sections of the ECCS Evaluation Model (EN):

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1. The switchiry:J of OIF correlations; from BAW-2 to IMC. _

2. An investigation of the applicability of the current CRAFT 2 core charuel ,

pressure differential ard flow distribution with respect to the MK-B8A fuel assenbly.

The use of the MK-B8A fuel assembly required a change in the CHF correlation used for IBIOCA licensing calculations6 ,7,8 frun the BAW-2 correlation to the 14

t ,. h. . o l 86-1176204-01 BWC correlation. 'Ihe IMC correlation, which was licensed for' use with 15x15 g fuel ' assenblies5, is mrrently used in the fuel design when MK-B8A type fuel ,

J assemblies are included. 'Ihe BWC corzulation has also prwen to be more '

limiting 6 than the BAW-2 correlation with respect to IBloCA calm 1ations. It is t

uruleretood that the currently licensed OF model for ECts use is BAW-2, and the ECCS evaluation model (EN) has not been updated to include the use of the BWC oorzulation for IBloCA calculations. Hmover, it was concluded that the BWC OF correlation should be' incorporated for the TE IRicCA analyses because:

1. 'Ihe NRC has accept:ad IBIOCA limits for the 177 FA lowered-loop plants in ktlich the INC OF correlation was incorporated6 ,7,8,

2. 'Ihe IMC OF correlation provides more limiting IOCA limits than the BAW-2 ,

correlation 6,

3. 'Ihe BWC correlation is currently used for the fuel design of MK-B8A type fuel asamblies5 , and is considered a more accurate OF oorzelation for the MK-BBA type fuel assenbly than the BAW-2 correlation.

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'Ihe effects of the MK-BBA fuel assenbly with respect to the core unrecoverable pr-3 drop and core flow distribution were evaluated. 'Ihe MK-B8A channel

/ unrecoverable pressure drop was found to be 0.4% higher than the pressure '

l differential presently used in the GAFr2 model. Because of this relatively insignificant pressure drop change, the CRAFT 2 pressure and flow distributions were not changed; a 0.4% increase in core unrecoverable drop is estimated to

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have a negligible inpact on both the total system flow and core flow l

distribution. In addition, the current GAFT2 licensing Itodel system flowrate, l

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86-1176204-01 which is ha==4 upon design data, is aproximately 10% lower than the measured system flowrate, thus ensuring conservatism for IBIDCA calculations.

In conclusion, the fuel configuration that was assumed for the IBIDCA analyses f

reported herein has that of an entire oors of MK-BBA fuel. BOL conditions were  !

assumed, whidt maximized fuel temperatures and thus represented the most limiting time in life for IBIDCA evaluations. The assunption that the entire e core consists of MK-B8A fuel is beurding, in that, at BOL, the fresh MK-B8A fuel tenparatures will exceed those of the once ard twice burned MK-B5 fuel assemblies. The BWO corzulation was aglied, in accordance with both fuel design requirements as well as IBIDCA requirements, to the entire oors. The configuration' analyzed for the Cycle 7 reload is thus bounding for the mixed ,

core as well as cpplicable to future cycles in which additional fuel asamblies with zircaloy spacer grids are aMai.

l 3.3 M FUEL IATA i 2he initial fuel tenperatures ard pin pressures used for IDCA initialization were obtained frun 7ED2 MK-B8A fuel data. The MK-B8A fuel design included a l

l reduced pin pre-pressure resulting in lower BOL internal pin pressures than the l' MK-B5 fuel. This internal pin pressurs reduction provides a slight advantage for IDCA calculations. In addition, the MK-B8A fuel tenparatures are nearly 1

identical to those of the MK-BS design at the same IHR.

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4 86-n76204-01 The MK-B5 DCD2 fuel data was used in the previous 2 and 6 ft IOCA analyses 4 3 Therefore,' a slight bannfit is expected in the use of MK-B8A fuel data due to >

L the reduction in initial pin press.tre at the 2 aM 6 ft elevations.

i The fuel code used for IDCA initialization for the previous 4, 8, aM 10 ft elevations 2 was TA!Y. The nFY fuel model overpredicted the initial fuel densification, thus yielding higher initial fuel pin temperatures and lower initial fuel pin plenum pressures than the BCD2 fuel model21 An NRC l

restriction was mandated when using the TAFY fuel data for ECX:S applications, requiring a multiplicative constant of 0.75 on the transient gas gap heat transfer coefficient to compensate for non-conservatisms in the model (specifically, fuel pellet - clad interaction). The multiplier was thought to ,

be conservative but proved to be somewhat non-conservative for the elevations in .which the peak clad tanparatures were nhaarved in the ruptured node.

l Following rupture, the heat transfer between the fuel and the cladding is governed by radiative heat transfer. MaximizinJ the heat transfer frun the fuel to the cladding results in the most restrictive IDCA limits for elevations I

whidt are ruptured node limited (i.e., historically the 2, 4, and 6 ft elevations). The multiplication of the gas gap heat transfer coefficient by .75 L

resulted in the storage of additional energy in the fuel, which could have been lf l

transmitted to the cladding to facilitate metal-water reertion.

t 3.4 FHXEET REFT. COD HEAT TRANSFER CORREIATION All previous Davis Maama IBIDCA limit analyses have included the FIKKA and i-REFIB2ff reflood heat transfer correlations to calculate reflood heat transfer 17 i

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1

t -a  !

.. j i

e 4 86-1176204-01 )

i coefficients for use in 'ItETAl-B. 'Ihe IBIDCP, analyses reported in this hW '2 F' , . I incorporated the TIECSET coryutar cu$e, whim uses the B&W modified FIR 2fr- i SEASET correlation 22, for the calculation of reflood heat transfer coefficients. ,

i\'

3.5 ECCS SYSTDE - HPI/IPIfCFT ,

i 3.5.1 HPI/IPI l 1

Within section 4.7 of the B&W topical repcrt BAW-10105, Rev.1, it was reported that the failure of an energency diesel generator subsequent to a loss of offsita power (IDOP) results in minimm ECCS during a IDCA. 'Ihe limiting ,

single- failure results in actuation of the motor driven DCCS systans (one IPI .;

train) 35 seconds after the IDOP. In addition, BAW-10105, Rev.1, states that HPI flw is not assumed for IRIDCA calculations.

i o ,

Following submittal of BAW-10105, Rev.1, the NRC requested that B&W address the condensation of ECCS injection fluid (i.e. , HPI) with r%-t to steam whid ran=a= the ECCS injection ports. 'Ihe B&W response23 concluded that the 9

oorxlernation of ECCS fluid resulted in slightly lower refloodinJ rates (1% to f 2% lower ) and slightly higher peak cladding tarporatures. 'Ihe current REFIDD3 model includes E0 3 condensation, and is diam --M below.

ECCS injection followinJ a IBIDCA currently consists of CPT, IPI, and HPI flow.

one IPI punp ard one HPI punp are assumed available in accordance with single failure criteria. However, one half of the HPI flow is ===M to exit the break and is therefore neglected. In this study IPI and HFI are aS=M to 18 r

.-2 al---- . + . . , . . - -

, - - -..c.-,. - --..- .,,.,--, , , , ~~ ,

. .,,,,w, -

a , , ,, , , , , , , ,- -

86-1176204-01 initiate sism11taneously following a 40 second delay after a low pressure (1515 psia) SFAS signal (Although the raised loop 177 FA plant has separate HPI cad IPI initiation setpolice, for the specific scenario analyzed, sirmtltaneous  !

HPI/IPI initiation is conservative). h time delay for EOCS injection was increased frta 35 to 40 seconds in order to provide TE with additional margin for actuation of their motor driven ECQi systems. Additional cold leg resistance was added to and of the cold legs in the REFIOD3 model in order to ,

aoocunt for a .25 psi pressure drop due to the csider-ation affect addressed e

above. 'Ihe IPI and HPI flow tables presently inplemented for TE IRLOCA analyses aru prueented in Table 3-1.

I I

i i

19 1

r; ,

, -1 l N:

86-1176204-01 1

TABLE 3-1 IPI AND HPI FLOW VS PRESSURE l

i.

LPI FLOW PRESSURE .5*HPI FIDW PRESSURE (GPM) (PSIA) (GPM) (PSIA)

L, 3307.5 15 0.0 1640.0 3307.5 35 257.5 1015.0 2722.5 95 318.0 615.0

l. .2250.0 135 345.5 415.0

t. e 1102.5 .195 366.5 215.0' l '

O.0 215 397.5 15.0 1 ,

3.5.2 GET Previous IBIDCA analyses have been performed with an initial CFP pressure of 600 psig and an initial liquid volume of 1040 FT3, both of whicti represent l.

I ncminal conditions. However, the TE Tactinical Specifications (TS) allow the CFP l

pressure to vary between 575 psig and 625 psig, and CFr licuid volume to vary i

between 1010 ft3 and 1070 ft3. In order to am --- - -hte the Technical Specification requirements with respect to CFr initial conditions, the following CFr conditions were chosen for the TE IBOCA analyses:

l Initial liquid inventory = 1000 FF3 ( 960 FF3 - TANK 40 FF3 -LINE) '

' Initial Pressure = 575 psig - 7 psi for instrumentation uncertainty = 583 psia l

Sensitivity stusiias 20 have shown that the reflooding rates are inwnsitive to  :

the TS allowable variation in initial CFr pressure (plus or minur 25 psi) . '

l I

20 l

g g , , , , - . . . . , - . . , - . . . _ , . . - . . --

-.--.w. . . . , - _ _ . , - - , _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ , - _ _ _ - _ _ . _ _. . _ _ _ _ _ _ _ _ - - _ _ _ _ - - _ _

s

^

A. .;;

g -

t - -

j Figure 3-1. B&W Model'and ORNL Correlation of Rupture Temperature as a Function of Engineering Hoop Stress 1

4 12W -

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! 1800-l i

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[ Figure 3-3. B&W Model and Consposite- NUREG Correlation of Reduction .

in Assembly Flow Area as a Function of Rupture Temperature r

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les -

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I e

i 86-1176204-01 4.0 REK7I.25 0F ANhlYSIS <

l

'Ihm results of this analysis are sunmarized in 7tble 4-1. A d4-== ion of the l risults of and BOL IDCh limit (i.e., 2, 4, 6, 8, and 10 ft elevations) is j contained within sections 4.1 thrtma$t 4.5. Section 4.6 addresses the a&iitional whole core metal 4mitar reaction due to the introduction of zircaloy spacer l l

grids. Section 4.7 addresses Cycle 6 operation (i.e., the current cycle of  !

cperation) wi'ch respect to the IfX'A limits established in this analysis. l l

Tisble 4-1 l i

f RZVISED EIlV. ATICH IDCA LIMIT INIfRIM tJ3Ch LIMIT-1987 BAW-10105-1915  !

(W/FT) (W/fT) ~ (W/FT)  !

2 FT 16.0 15.5 16.5  !

4 PP 15,75 16.8* 17.2  ;

6 FT 16.50 17.0 18.4 8 PP 17.25 17.5* 17.5  ;

t 10 FT 17.00 17.0* 17.0

• F ,- -- .ts IDCA limits which were estimatai based upon 177 FA lowered loop results. ,

4.1 2 FT ANMXBIS t The results of the 2 ft analysis are contained within Table 4.1-1 ard figures >

4.1-1 thrzu$14.1-2. A 2 ft peak linear heat rota of 16.0 kw/ft resulted in a ,

t ruptured nude peak clad tamparature of 2151.7 F at 35.4 seconds, ard an unruptured node peak clad tanparature of 1975.3 F at 34.5 seconds. A limar I I

heat rate of 16.0 kW/ft at the 2 ft elevaticri iv:- :its a 0.5 kW/ft increase with i+1 to the provicus 2 ft submittal (Ref. 2) . h, the revised analysis includes D atim Model (IM) nodifications, as dime =ad in Section ,

3.0, whim were not required when the provicus 2 ft mlysis was performed. 'Ihe inpact of each IN mradification was difficult to detarnine in that 4 changes .

24 l

_ __. _ _ ~ .

.-. _. . . . . - . - . . . _ . . _ _ - . _ _ , _ _ _ . , . , m.. _ _ _ _ . - - - . . 4-..,

l 86-1176204-01 waru performed simultanscusly. However, and modification will be a&iressed separately in an attempt to detamine eam relative impact. i l

l 1

TACD2 FUEL [171 i

)

The MK-BBA TA002 fuel data was used for 1DCA initialization for the 2 ft l alevatics) reported herein, whereas MK-B5 TACD2 fuel data was implenented for  !

3 the prwvious 2 ft analysis . The MK-BBA and MK-85 Th002 RX, fuel tamparaturns are emeentially identical, thus irdicating no advantage or penalty due to fuel  !

t tamperature differentials. However, the MK-B8A initial pin prussure was I l

asymcimately 200 psia lower than that of the MK-B5 fuel assembly. Since a mid  !

blcWdown rupture was cheerved in both the CPAFT and 71EIA runs, the benefit of  ;

the reduced pin pressure for the HK-88A fuel assembly was not realized. The  ;

impact of the use of TACO 2 at the 2 ft elevation was reported to be -0.5 kW/ft,

! with respect to the BhW-10105, Rev.1, analysis. No additional penalty or }

advantage is estimated for this analysis due to the use of MK-B8A Th002 fuel l_

data.

I l

i. A ocmparison of the IUGA ard ITESET reflooding heat transfer coefficients at i l  ;

the 2 ft elevation, assuming identical flooding ratas, power, etc., is provided i in figure 4.1-2. The FIECSET oorrelaticri predicts in:2 higher heat transfer coefficients ever the first 15 seconds following and of adiabatic heatup (IX*H) than the FUX:KA correlation. The peak clad tanparature at the 2 ft elevaticri was observed at 35 seconds, at whid time the !1ECSEP predicted HIC was approximately 4 times that predicted by FIECKA. The difference in the TIECKA I 25 1

- --~

[

I 86-1176204-01 i ard TIECSET reflooding heat trarwfor coefficient correlations has traditially l yielded an ircrease in the 2 f t IDCA limit of .5 kv/et (Ref. 15) . The same ircrease may be estinated for this analysis. l I

Edus IEI/HPI - CPT 7he BOCS rulated modifications (i.e., IPI/MPI delay and 07 parametars) did not result in a re&ction in cort flooding ntas with swA to the previous 2 ft ,

suksnittal. No reiction in the rate of core racmery was relized because the '

motor driven BOCS plaips wars actuated beform the OT's emptied, thus ensuring a downcanor level at the cold leg initt norrie elevation throughout the .

transient. Thereform, this change had no inpact on the 2 ft IDCA limit.

IMC QT CGtREIATION The OF oorrulation dictates the time at which the inception of INB mmns. A revision of the IM OF oorrelation, frun BW-2 to IHC, did provide slight differsnoes in the time of CNB incepticn at the 2 ft elevation. A sunmary of the time of INB ooourrence is provided below:

GAf72 BW-2 015.5 W/ft 0.5 seaands GAFT2 INC $ 16.5 W/ft 0.4 secords  !

THETAl-B BW-2 015.5 W/ft 0.7 seconds THE%1-B IMC $ 15.5 W/ft 0.75 seconds The GAFT2 IMC at 16.5 kW/ft predicted INB earlier than the GAFT2 BW-2 analysis at 15.5 kw/ft; howvsr, these runs are not directly ocmparable because 26

i o  !

l l

86-1176204-01 l of the difference in linear heat rates. The THETIAl-B runs, whim were both performed at 15.5 W/ft, resulted in the occurtance of INB at apprtadaately the !

t same timer however, they were based on GarT2 runs with different linear heat ratas, and diffarent rupture times. A ocuparison of the fuel and clad i

u tasperatures at EQhH, Wi& shculd reflect the diffarance in the INB l correlations, is not aplicable in this instance due to the diffaronoes in the QWFT2 analyses. Since the time at whis INB was cenarved differs very little f with respect to the THE'IA runs, it was concluded that the IHC correlation had ;

no .iap.tct at the 2 fu elevation.  !

9 vv of Results at 2 ft Elevation [

L 1he relative impact of each of the aforementioned parameters is somewhat subjective in that a direct quantification, whim .culd have required the ,

I variation of one parameter at a time, was not dene. Instead, a qualitative  ;

l ,

ammmmmment of the impact of eat of the IM acxilfications M--M above was made, and the .5 W/ft increase in the IDCA limit with respect to the previous  !

, 2 ft analysis was attributed to the use of 77.!XSLT reflooding heat transfer j i

coefficients. A surmacy of the estimated inpact of each of the above EM modifications is provided below: .

BAN-10105 m L1MIT 16.5 kW/ft  ;

TACD2 IMPACT -0.5 W/ft

• l NUREG-0630 IMPACT -0.5 W/ft *  ;

fuX5TF +0.5 W/ft .

IHC 0.0 W/ft  :

i 70IAL 16.0 kW/ft

• As identified in reference 3.

27 L

l 86-1176204-01 i

i e r 4.1-1 sueom or 2 rr nagu129 ,

i

?

CRAFT 2 IHR 16.5 kW/ft

'DETAl-B IJER 16.0 kW/ft CFT ACKETICDI 16.267 sec Dd of Blowtkam 22.30 sec  ;

Frd of Bypass 22.30 sec I

Liquid mass in W at BOB 1302. Ibn

• InhH 31.13 sec i

IDQB Punps on 40.5 sec  ;

i CIT's empty 41.42 sec Rupture Tins 12.41 sec  ;

PCT (nyt. node) 2151.7 F -

i Tias of PCT (rupt node) 35.24 sec ,

Pf.T (unnyt. nodw) 1975.3 F l l Time of PCT (unrupt. node) 34.5 sec  ;

l Max. Term 1 oxidatica 3.63  %

t t

l l

l l

28 .

4

.o -

3 t'~

• 86 1176204-01  :

I

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t en g j 3 ff r' -

. 33 .

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m E

R 8

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R l-B U

B E

j ' aange a adwaj. pu t o a6e a any 29

E'.C02 i

5 4

i 2

e h

t e 3 t 4 a

no i

s i r

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1

- - - - - - - - - - - - _ - 3 1 0 91 8 1 7 16 5 41 31 2 1 1

0 1

9 8 7 6 S 4 3 2 2 2 1 1 1 ,

iIpCN3m . E~uc o ee%Ce aOeI e

4" i

86-1176204-01 l

[

4.2 4 FT ANAIXSIS The results of the 4 ft analysis are premonted within Table 4.2-1 and figures 4.2-1 thrtugh 4.2-4. A peak allowable linear heat ruta of 15.75 kw/ft was  :

I calculated for the 4 ft elevation. The peak clad temperatures of the ruptured  !

i e and unruptured nodes were 2049.46 F (0 40.77 scoonds) and 1954.3 F ($ 82  :

I seconds), twpectively. The 4 ft IJR of 15.75 kW/ft represents a significant  !

reduction frun the interia IJ1R of . 6.8 kW/ft. Prior to this evaluation, the 4 l ft loCA limit had not been analyzed since 1975. f f

i The Dt &anges, noted previously in section 3.0, contributed in varying degrees i

to the re$uction in the 4 ft IJiR. The inpact of each D( change has been estimated as discussed below.

1 TAOD2 VS TAfY  ;

i The previous 4 ft analysis 2 ir/JoIporated the TAIT fuel Code for the Calculation of initial fuel parameters for use in IDCA calculations. The 7AFY gas gap heat i i

transfer coefficient concern, as diamamed in section 3.0, was addressed for j TE21 via an analysis in which the gas gap nultiplier was ctarsped frun .75 to [

1.0, for the 2, 4, ard 6 ft elevations. The 4 ft elevation was able to l e

aoocanodata the increased heat flow, and no IJR inpact was assessed at the 4 ft elevation.

The TACO 2 MK-B8A fuel data implemented for the IDCA reanalysis provided lower ,

fuel taperatures but slightly hights pin internal pressures than the TAfY  :

data; the net result of which was an estimated cancellation of these tvo P i

31

. . - . , w ,,-.---,.,------m- . . . - - - - , , . - - - - . . . - -. - - - - - - - , . . - - - - - ,e . - . . . . - +

• I i

'4  !

i 86-1176204-01 j effects. With no ret effect resalting fran the ctarge to the gap multiplier, l l

ard no imact &m to the revised fuel tasserotures and pin pressures, it was estimated that TA002 had no igact at the 4 ft elevation. ]

I NURB3 - 063010PIURE CURVES  ;

The NURB3-0630 cladding Impture carves are more limiting than the previcusly enployed BW claGiirq rupture data, as dianM in enction 3.0. Since the 4 ft .

t elevation is tmptured ncde limited, the revised rupture curves had a negative i L

igact on the 4 ft IOCA limit. The igact is estimated to be 0.4 kw/ft, as is explained in reference 3. j I

t FIEQSET RETIDODW l A ocuparison of the 4 ft heat transfer coefficients (IfIts) predicted by FIECSLT to tht: of FIEC3%, for identical bourdary conditions, is presented in rigure 4.2-2. Wille the TIECSET predicted Hits are initially larger than those 1 i calculated by FIECKA, the TIEC*A Hits quickly ircrease above the TIECSET 1rIts, i ard am aproximately a factor of 2 higher at the time when the peak clad 5 t

tamparature at the 4 ft elevation was aboarved (11 seoceds after IDAM) .

Therefors, the icwor rursLT HIos at the 4 ft elevation relative to those praiicted by TIE 3A may have resultad in a IHR penalty. ,

After cxmparing the FIECEA and FIECSET heat transfer coefficients at the 4 ft elevation, a ocuparison of the TIE 05LT heat transfer ocefficients for the 2 ard 4 ft elevations was made (rigurs 4.2-3). The flooding rates, peak power, ard all remaining boundary conditions for the 2 and 4 ft elevations were similar 32 I

f e

\ _ -__ _ _

i i

l 1

86-1176204-01 j ancasA to justify a ocuparison. The hit;$ MC for the 2 ft elevation over the {

first 20 seconds followirsir M, when ocupared to the MC prettetad for the 4 i ft elevation, is very beneficial with r ct to the mitigation of metal water heating, particularly in the nptured node. The large din +cy in MCs between the 2 and 4 ft elevaticris contributed to the reduction in the 4 ft UR l l

below that of the 2 ft.

ECCS IIIAY  !

The Ecos delay and variation in C2T initial parameters resultad in negligible

! flooding reta differences, as Mmwaad in section 4.1, ard are estimated to l t

have had no inpact on the current IOCA limit. '

IMC CHF 03tRE2ATICH ,

The IMC oorrelation resultad in an earlier predicted hot channel INB than the  ;

IAW-10105, Rev.1, 4 ft IDCA limit (0.4 seconds in prvvious THETA run 17.2 f kW/ft - less than .1 seccrd for a IMC THLTA analysis 617.00 kW/ft). In order  !

to ansees the inpact of the IMC CMP oorTelation, a ocupleta 4 ft re-analysis r with the BAW-2 CEF oorrelation was ocupleted and is reported below. l In the reanalysis of the 4 ft elevatict), cnly the CHF oorrelation was changed, .

i.e. , fran IMC to BAW-2. A linear heat rate of 16.25 kw/ft in CPAFT and THLTA ,

resultad in peak clad temperatures of 1767 F (40 seconds) and 1951 F (85 seconds) for the ruptured ard unruptured nodes, r+tively (Figure 4.2-4).

Since the 4 ft analysis became unruptured node limited, (i.e., not limited by metal-w. tar reaction within the first 20 eeoonds following m) it is .

33

,., - . . . --. - - ,. ~ . . - . ,

t l

86-1176204-01 I l

estimetad that the IfX:A limit oculd have been iruh by as nu& as 0.5  !

I W/ft, to 16.75 W/ft, without = Ming the 10 CHt50.46 PCT limit of 2200 F. j

'Ihe increase in the 4 ft IDCA limit frun 15.75 W/ft to 16.25 W/ft, was due to the implesentation of the BAW-2 OF correlatitm, ard the ec - 7:=.t impact i of the BAW-2 Of correlation on pre and post CHF heat transfer and core  ;

I flewrata. 'Ihm following oanparisons were made between the CRAFP2 and 'IHETAl-B l t

rum, with r+t to the time at W& the het channel experienced INBt  ;

i CDGUITR KMB TIME OF INB l GAFT2-BhW-2 016.25 W/ft 0.50 sec ,

CRAFT 2-IMC 016.25 W/ft 0.25 sec i

'IHEIAl-B BAW-2 0 16.25 W/Fr 0.35 sec

'IHEIAl-B INC 016.25 W/Fr 0.04 sec i

As notai above, the time at which the hot channel e.h INB, for both GAFT2  !

and 'IHEIAl-B, was earlier in both occasions for the BWC analysis when cxmpared ,

to the BAW-2 analysis. 'Ihe earlier INB for the 4 ft IMC case contributed to the retentian of more energy in the fuel &aring blowdown, ard thus resulted in ,

hipar fuel and clad tanparatures at EQAH. 'Ihe increased heat flux d.a to higer (

fuel tauperatures yielded greater clad tenparatures which in tum elevated the rata of metal water reaction. In order to offset the the effects of an earlier  !

IND inception due to the inplenantation of the IMC OF correlation, the DR (initial stored energy of the fuel) had to be rMv=4. 'Iha discrepancy between 34

-- , --m, .-. - ,a ---.- --- .w--.-- . . , - . ,

I i

I 86-1176204-01 l CRAFT 2 ard 'DIL%1 B INB praiictions ocx:urred because the QEIT2 code uses l unfiltered ficw for OF omloulaticris whereas ' atrial-B uses filtared ficW. l l

'Ihm sigrtificant reduction at the 4 ft elwation was attributad primarily to the ,

implementaticm of the IMC OF oorrelation. Of the 1.45 kw/ft reduction with ,

r p-ci, to the BAW-10105 limit, the OF oortulation was responsible for at  !

least 0.5 kW/ft and prubably more.

i 9==aarv of the P-its at the 4 ft Elevation i

'Ihm relative impact of each of the aforumentioned IM m:difications with respect to the previcus 4 ft IDCA limit reporte:1 in BAW-10105 was estimated as follows:

r 1

BAW-10105 limit 17.20 kw/ft TACD2 inpact -0.0 kw/ft * ,

NUREG-0630 -0.4 kW/ft *  !

(INB. INC/fuCSET -1.05 kW/ft i

'IUrAL 15.75 kw/ft l

• As specified in referurces 3 and 4  ;

'Ihe 4 ft alwation exhibits a nut earlier transition into IND than the 2 ft  ;

elevation, thus storirug more energy within the fuel during blewdown. 'Ihis i earlier INB in ocabination with the significant difference in refloodirq heat transfer coefficients, resultad in the reduction of the 4 ft IDCA limit belcw l the 2 ft IDCA limit.

1 L

I 35

- , - , , , - - - . . . . . ..m3 . _ . - - . . , . , . , , _ _ , _ . _ , . , , , . - . m , , . .__.,,7 . , . _ _ ,

r r

i

.. i s ,

86-1176204-00 I i i

i Table 4.2-1 1 SLM9Jtt OF 4 FT LOCA LIMIT A1& LYSIS .

i CPAFT2 IRR 16.25 kw/ft ,

t

'DETAl-B 15.75 kW/ft )

1 CPR ACIt1ATION 16.36 sec .

End of BlowdcWn 22.4 sec FJd of Bfptas 22.4 sec '

Liquid Mass in RV at EDB 1321 lbm EOAH 31.22 sec .

ECCS Purips on 40.7 sec ,

CPI's Dtpty 41.7 sec Rupture Time 22.4 roc l PCT (ruptured node) 2049.46 F Time of PCT (rupt. node) 40.77 sec PCT (unrupt. node) 1954.3 F Time of PCT (untupt. node) 82.0 sec Max. 1e m i Oxidation 4.98 %

e 36

Figure 4.2-1. 'Iheta - 15.75 kw/ft at the 4 ft Cbre Elevation 2000 LEGDO

^

Level 4 Ruptured

- - - * - - Le ve I 5 t.hiruptured 2400-Ln.

U A

p

$2000 '

.=-m w.,,

e ,, .. ,.M*

L '4.,M.

i .

'". .' unng*ured mxie w

I-- 1600-w

.- N ~~ . ,

n D w*

m .f .

w O 4 ,

h*3 et 4,

. O R 4Aured Node \

• G

• 1200 -

L N *.

O .

> 4

[ .

". ~

=,

800-N c)

N *N -.

ea

% 'n'*

400 m C ru 20 40 60 80 100 120 140 ISO 100 200 LOCR Time, see 220 240 h S

- - . . . . . ._- _ - . - .. . .. _ _. .w

l t

i Figure 4.2-2. Flecka vs FlW Heat *Pransfer Coefficient Omgarison at the 4

, et oore Elevation f

~

1 CM i,

os i

g .

RECKA E

i zq _ R 5mT 3

d t-e v -!

a_s 3 0 O ,

iE SL

g us j O 20 i o E

i -

us . - - -

. m ,

es -

~~~~.

1

$10 -

. . - ~_---_------ ---

F-i n- .-

s I I EO ' ' ' ' ' ' ' ' '

O 10 20 30 40 50 60 70 80 90 100 *.

T54E FOU_OMNG END OF ADUEATC HEATUP (SEC) Ee l

N O '

• =

0

. O i

• -* t en_ 4-e- ph wew e,- y v *- yT d -*-- wwNW *m v w'e

&9"**4 9'v'*umwhW- 9-9Mw-w'e-v9" w ewsw- yev we _-ww__e-e'N___e*-u-- m_ e- hwa-sia - %____ %- _ ew nr-_--h---hw ade--m- - - -na-w1_ w

) t yCygPS 0

2 .

. 8

- s t _

1 n '

i e

c i

f 6

- f .

. e 1 _

. c O

r f

e s

n a

1. 4 1

C T

t r

a

+ E S

i Pr H

e P

• 2 U T 4 t 1 A

f W E _

4 , / H d C+

n I T

a t

T

/ 0 1

A B

A I

/. D 2

/ A t

e s

e - ./ / F O

l F

e k

_V l 8 DT 4 r t

E 2 f

o R E

n o

s /' / 6 T

Fa i ' A r

A ( E MI

% W T

/, 4 s' -

3- I'/

2 4

ju i/

/ .

e r

u g

,frc l

2 i

F .

su 0 i6 3 0 9 8 7 6 5 4 3 2 8

1 l 1 3 4

1 u2 1 1

1 1 xd A['ae .sw a~ o" r t en k g s4 t

g

Figure 4.2-4. 'Iheta - 16.25 kw/ft at the 4 ft Cote Elevation -- 5082 %

2000 . . -

2000 g%%%%%%%%g W Node NN t

~t <'

,4

.**.g..,%

6 G -6 #

'g 4

1750-- V *

= -1758

• f g

^

J w A

k q b AgF v kssg e 6 A L 1500 .

A", ISM

+>

3 -

l 6 m f

• L e Rupttated Node k O j .

k E ,ow' a g" 1250- * --1250 s o m

t m U ,

'ec) 1000 1e.30 m

L e

T l 750- -750 node 4

. . . * * - *

• node 5 g

. . . - c . . - node 6 L node 7 O

500 . 5m g; O 8 IG 24 32 40 48 SG G4 72 08 OO 96 104 112 120 120 g Time (sec) h

t

' i f

• t i

P 86-1176204-01 l i

4.3 6 FT ANhlXSIS  !

I The results of the 6 ft analysis are presented within Table 4.3-1. A lirmar l heat rata of 16.5 kW/ft resulted in peak clad tamparatures of 1826.5 F (38.5  !

seconds) and 2176.18 F (111.76 seconds) for the ruptured and unrupturwi nodes, respectively. The rwturwi and unrg tured node cladding tamparatures are  !

presented within figures 4.3-1. The 16.5 kw/ft IDCA limit obtained in this  :

L analysis represents a .5 kW/ft re&ction frun the prwvious 6 ft analysis4. The  :

prior suknittal included both Th002 (MK-B5 fuel) and NUREG-0630, but did not l include the following significant D( changes: '

1. IMC QF oorrelation l

2. TIESET reflood heat trarsfer coefficients i

The previous 6 ft analysis incorporated MK-B5 specific TACD2 fuel de.ta which l predicted BOL pin pressures asprtatimately 200 psia higher than the MK-BBA TACO 2 j data used in this analysis. However, the advantage of the reduced pin pressure l was not estimated to be significant because a mid-blowdown rupture was ,

predicted in the CRAFT 2 simlation. No difference in initial fuel tamparature was observed, thus no advantage or penalty due to initial fuel tamperature  ;

difforentials was realized.

The 0.5 kw/ft reduction, fran 17.0 kv/ft to 16.5 kw/ft at the 6 ft elevation, was attributed to the implementation of FIRSET reflooding heat transfer  ;

coefficients. The contribution of the use of the IWC OF oorrullation was found to be negligible. When ocuparing the time of INB oetween the previous arxi 41

,_.,___,___._m_,.y., . , _ . _ _ _ . . . , , _ , . , . .

l- 1

. \

l ,

o j 86-1176204-01 ourrent analyses, no significant difference was found for either the CRAFT 2 or l 7HEIAl-B runs. In addition, a 17.0 kW/ft IMC '.tHE'IA calculation was ocupared to f 1

a 17.0 kw/ft BAW-2 THE3A run. The clad and fuel tamparatures wers ocupated at j InAN and were found to be in cloes agramment (i.e., all average fuel and  !

average clad tamparatures agreed to within plus or minus 25 F). The potential negative impact of the ISC OF oortulation with r+t to predicting earlier f INB inceptican was therefore ruled out for the 6 ft elevaticn.

I A ocuparison was also made of the FUXSET and FIECMA heat transfer ocefficients [

for the 6 ft elevation at 17 kw/ft (figurs 4.3-2), assuroing identical boundary j oonditions. Fran the ocuparison, a significant difference in heat transfer ,

ocefficients exists after 40 seconds, with the FUXSLT heat transfer coefficient prediction approximately 40% to 60% lower than FIECKA over the ,

interval in Whicts peak clad tanparatures were observed (40 to 180 seconds). The large difference in reflooding heat transfer coefficients is estimated to have -

resulted in a .5 kW/ft reduction of the 6 ft IHR, with respect to the previous ,

i analysis.  !

i k

9 i

L 42 e

,. . _ - . , - - . ,y-- . . . _ ,--- . ,

I i

e h 86-1176204-01 23E31v of the Daant1ts of the 6 ft Elevation {

The respective impact of each of the D4 nodificatiwa has been qualitatively namansed and is surenarized below:

1 BMf-10105 limit 18.4 W/ft TA002 -0.0 W/ft NUREG-0630 -1.4 W/ft

• IMC -0.0 W/ft  ;

FIECSIT -0.5 W/ft t

7U."AL 16.5 W/ft

• NUREG-0630 penalty assessed in zuference 3  !

t I

l l

t i

1 43 l

l i l

i 1

F L

l.L 4 i

.d. I j}.

l

'i  !

86-1176204-01 j

)

1 t

TMII2 4.3-1 ,

l SG99JN OF 6 FT IERT125 (

GAFT2 IJR 17.0 kW/ft  !

I

'IHFIAl-B DR 16.5 kW/ft j CPT AC'RATIQ4 16.2 sec 1 End of BlowdcWn 22.1 sec  ;

i End of Bypnas 22.1 see -l Liquid Mass in RV 0108 1320.00 1ha ,

1lDhH 30.87 see EOCS Peps on 40.7 sec j CIT's Enyty 41.4 sec j RLyture Time - CRAFT 2 017 kw/ft 14.38 sec >

'IHFIA 016.5 kw/ft 21.88 see i ICT (nyt. node)- 1826.50 F i e

e Time of PCP (rupt. node) 38.50 sec PCT (unnyt. node) 2176.18 F i

Time of PCP (unnyt. node) 111.76 sec Max. Tmal Oxidation 2.91 %

i i

i 44 i

3, . _ -

.-.e ,

86-1176204 01 l .

i f

f

~

s l

8

'3 -

r t

? s 25 J g l 5* w s ~

yI 6 5 r

d

/

e*

1h s i II a A I u

1 A g l 1

2 - '

b r 1 '

1 4

• 5 -

J -

7 s 4 .

x d e E '. E 4  ;  :

J l s 1

- 8 i

"B M =

w , .

Y gno  !

$  ?

r . N a* A e 8" M ", $

h , ,

J e-ss A > j]

~

~h n 5 ,

? -

• , *, i

. /

I

,i r

/ 7 i R

t u.

g ' r. R l it 'r, L

1 .. e

- N

. S y .

I 3 $ 3, u

m

~

=

N C 3) 8Jnteaadwal Pe l3 e6eaeag .

45

1

<. J Figure 4.3-2. Flecia vs Fl(K Heat Transfer Coefficiemt camparison at the 6

• ft Core Elevation - )

24

+

22 -

20 -

I -

18 -

l l 16 - -

@ 14 -

Y E i2 - <

g t

- 10 -

x 8-6-

4-2-

E O4 , , , , , , , , , , , , , , , , , ,

~[

0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 160.0 180.0 3 2

TIME (SECOND$) [,

O FLECSET DATA + FLLCKA DATA ~

. . _ . _ _ . . _ . . _ . --_ _ - _ , _ - _ _ . _ _ - . . _ . . ~ _ . _ ._ . .

r i

86-1176204-01 l 4.4 8 Tf ANAINSIS

'Ihe results of the 8 ft aralysis are stannarized in Table 4.4-1. A peak linear f heat rata of 17.25 kW/ft resulted in a peak INptured node clad tastparature of l 1803.4 F at 80 seconds, and a peak untyptured node clad temperature of 2164.20 F at 155.0 seoords (Figure 4.4-1) . 'Ihe revised 1DCA limit of 17.25 kw/ft r represents a .25 kw/ft reduction frtza the intaria loCA limit. 6 i

'Ihe 8 ft 10CA limit had not been analyzed since 1975 'Ihn interim 8 ft 10CA  !

limit 4 was ha==4 entirely on the original loCA limit (BAW-10105, Rev.1) and an extrapolation of 177 FA lowered loop plant results. 'Iherefore, the current  ;

analysis is the first time in which all of the D( updates listed in section 3.0  ;

were included in the 8 ft evaluation. l Since all of the D( modifications were performed similtaneously, the inpact due ,

to ends of the acxilfications nust be ammersed qualitatively. .

t TACO 2 VS 'IAFf l '1he initial fuel temperatures and pin pressures inplananted for the previous 8 l

l ft analysis were provided by the TAFt code. 'Iha 'IACO2 MK-BBA fuel tanparatures l

, - were lower than the 'IAFY data, as describel in section 3.0. In addition, the i fuel pin pressure used for the previous 8 ft analysis was approximately 300 psia higher than the pin plessure used for the present analysis. 'Ihe pin pressure was increa==1 in the previous analysis to force a mid blowdown rupture. Since the fuel tanperature and pin pressure were both lower for this 47 e

,----eru- ,,v-. -p--- - - - , , , , , _ _ . , - . , , . , - . , , - - - , , . , . , , - - , , - . , , . , _ , , -n-

I l

.. j i

86-1176204-01 l armlysis, ard the unnptured node yielded the highest peak clad temperature, i

the impact due to the use of TMD2 was estimated to be insignificant.  !

I NURID-0630  !

The NUREG-0630 rupture curves are more limiting than the previously used EW  :

rupture curves, and have been shown to result in earlier rupture times nrd I e:' y---it higher ruptured nodo peak clad temperatures. However, the peak c..ad j temperature at the 8 ft elevation was nhamwed in the unruptured node. NUREF l 0630 inplementation was therefore assumed to have no significant impact on the l IDCA li: tit at the 8 ft elevaticri, i

i FLECSET REFIIXCING HEAT TRANSFER CDE2TICIINIS i I

All pzwvious IDCA analyses have incorporated the FIZGA code for calculation of reflooding heat transfer coefficients. The recent approval of the FIECSEP code }

resultad in the use of FIECSEP for these analyses. A comparison of FIEC3% heat i

transfer coefficients used for the IEW-10105,Rev.1, analysis and the FIECSEP  !

heat transfer ocefficient predictions used for this analysis are provided in  ;

figure 4.4-2. No significant difference is obee::ved, thus no impact is  !

estimated for the use of the FIECSEP }fIC code.

t f

i p

4 l

48 O

i

\

86-1176204-01 i I

rx:cs rmy - crr rumAL amomms  :

nm tocs delay and variatien in CFT initial parametan resultad in negligible j

.ficading rata diffemnoes when ocupared to the prwious analysis, and ars l estimetad to have had no impact on the curzwnt IIX:A limit. l IMC OF CI:EERI2ATIM A omparison of the time to enter DNS was made for the current and previous analyses at the 8 ft alwation. The results are sumarized below: l i

CRAFT 2 BAW-2 417.5 kW/ft < .10 see GAFT2 IWC 4 17.5 kw/ft < .10 sec 7HETA1-B BAW-2 417.5 kW/ft < 1.00 sec 6 THrIAl-B IMC 0 17.5 kw/ft < 1.00 sec A ocuparison of the THrIA prelicted average fuel and cladding tanparatures at  !

EDAH showed clad arx1 fuel tanparatures between 110 F to 150 F higher for each of i

the 7 THrIA axial segments for the IMC analysis. It was therefore concluded I i

that the IMC OF oorrelation did inpact the 8 ft analysis, and was risponsible i for the .25 kw/ft reduction.

P 9menaW of Mats for the 8 ft Elwation i The relative inpact of each of the aforenantioned EM modificaticns was determined. A 0,25 kw/ft reduction was attributed to the use of the IMC OF oorrelation. The results are sumarized as follows:

I 49 1

\

\

1 86-1176204-01 l l

t i:

L BM$-10105 limit 17.5 kv/ft -

[ TACD2 impact -0.0 W/ft  !

NURIG-0630 -0.0 W/ft

F1JDQErr .-0.25 W/ft

IUXSET 0.0 W/ft h MIAL 17.25 W/ft i i

e I

l

?

1 t

i

?

I t

f i

t I

l 4

9 i

i b

I' ,

I i

1 e

l 50

I

.s ,

i s. ,

' i

' l t

' 86-1176204-01 l TAntr 4,4-1 f SO99JOf.OF $ FT RESULTS t E, CPAFT2 U R 17.50 kW/ft  !

H ETA 1-B U R 17.25 kW/ft CFT Actuation 16.31 sec i

End of Blowdown '22.20 sec  !

i l

( .End of Bypass 22.20 lha I

i Liquid mass in RV at IDB 1345,00 1ha i

ECM 30.97 see ECCS Punps Cn 40.70 sec [

l CET's Enyty 41.44 sec  !

Rupture Time 15.34 sec  !

PCT (rupt. node) 1804.00 F ,

Time of PCP (rupt. node) 100.00 sec i l

PCT (unrupt. node) 2141.76 F

,~

Time of PCT (unrupt. node) 129.13 sac  !

1

! Max. Local Oxidation 4.44 % l t i i

f 1

l' 51 t

l l

, - ,. ~ ,w- ,a -

-e , - , - , , - , , - - ,- -- --

g '

n

-. 7

, e r 3-Figure 4.4-1. 'Iheta -'17.25 kw/ft at the 8 ft Otre Elevation _

/

2000 . _ gges

- LEGDG nooe 3

. . . . g . . . . mg 4 i .

2400- -

--2400 n

ls.

1. * - Unnytured Node L 2000 ' +'-

2006 3 N to y y L

.w w w 4.w ., A g O

"4 w '" g . 4 ,, 4 w.g'4 'w., A A

g gO 1600-- ,- '"~4-w., N --1600 V

44, m

m m -

~

g ^ .'

Ruptured Mode '" g

,g

. j- w e) fy w cn 1200  ; 1200 m

L

)

4 4

g .- 4 m

h" 000- - --800 m

cn w

W w

4m 400  %-

0 20 40 60 80 100 120 140 160 188 200 220 240 250 280 300 320 2 Time (sec) E

, , , - _ - _. , _ . - - . -- - _ _ , . . . . . -.. . - - - . - _ . - ~ .

.- . - - - . , ~ .

- . . - ~ - - - - - . . . = -

o a Figure 4.4-2. Flecka vs Flecset Heat Transfer Ocefficient Omuparison at the C' ft Gore Elevation ,

20 19 -

18 -

17 -

16 -

15 - 'i 14 -

n 13 -

k N

I 12 - ~

'i'~T  : s n==R C II -

i

( 10 -

9_

f in 8_

v I 7-6-

5-4-

3-2-

1 -

0 i i i i i i i i i i i i i i m m

0 20 40 60 80 100 120 140 '

O TIME AFIER EOAll (SEC)- h ItLCKA + f t.ECSE1 *

(x

~. . _ _ _ . ._

. . _ . . . . . . . _ . . ~ _ _

i o

..~;

86-11'i6204-01 l

l 4.5 10 PT ANALYSIS The results of the 10 ft analysis nre prese7ted in Table 4.5-1. A linear heat rato of 17.0 kW/ft resulted in a =4== unruptured node clad tenparature of ,

1849.62 F at 169.31 seconds (figure 4.5-1) . h peak ruptured node clad ,

tanparature occurred at 34 seconds and was 1609.7 F (figure 4.5-1) . The 17.0 kw/ft limit is identical to that reported in both BhW-10105, - Rev.1, and the -

interim IDCA limits subnittal4. The 10 ft analysis was similar to the 4, and 8 ft analyses in that the last IOCA limit performed for these elevations was in 1975. None of the D( model modificationa listed in section 3.0 inpacted the 10 ft LOCA limit. .

s 54 4

- ~---n. - - - - - -_ _ _ _ - _

^ ,. .-' (,

' ' .; e . * .

, Js; ,

86-1176204-01 d-TMIIZ b.5.-1 SG99JW of 10 PT RESULTS .

GAFT2 IRR' 17.0 kw/ft  :

'IHimL1-B IRR 17.0 kW/ft ..

1 CFP ACIUATION TIME 16.2 sec DID OF BILWDOW 21.9 sec f r

DO OF BWASS 21.9 sec M TER in RV AT BDB 1408.0 lbn l EDAH 30.62 sec >

40.7 sec i Time ECCS punts on

' Tims CFT's engty 41.5 sec  ;

Rupture Time 24.6 sec PCT (rupt. node) 1609.7- F l' TIME of PCT (rupt. node) 34.0 sec l ',

PCP (unzupt. node). 1849.62 F 1.

L Thne of PCP (unrupt. node) 169.31 sec L

L' 1

Max. Incal Oxidation 3.17 %

L <

1 1

l l

P 1

i..

55 i

e e v , - -

~

• $ '. O nN

< g. ow e

0

' - ' ~ 6 3

34 ee

- dd -

oo D nn N 0 E

G 2 E

3 L

e d

o ~ .

M ,

d 0 n

o e r

~ 0 2

i t u a t v p ~

e u r

l E n U

e r

- 0 4

o 2 C

't e

d f o 0

1 A. ~

N c e-e M ms h u t - t t 2 ,

p e t u a R m f

t _ i T

/w , O k ) S c.

I 0

7 1 -

a , s e t h e t h

I 1

5 4 g - 0 e 8 r s u

g i

F -

g 0

\ 4 7

- O 0 0 0 0 0 0 0 0 0 ,. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 , 0 8 6 0 0 6 4 2 0 8 6 1 , 1 3 2 2 2 2 2 1 1 1

2 UL3$ leo.Eo& 0 1

T2o ef g E

l! ., l I 1,'. l -

" * * + - m-J1.u. _ , , _ , , , ,

k

+

86-1176204-01 o

4.6 F90CIMM ifYIBOGEN GENERATIQ4

'1he Cycle 7 reload represents the first time in which fuel =* lies with ,

zircolay spacer grids are to be inserted in the DB-1 core. The incxarporation of additioral zircaloy required a reassessment of the whole core metal water reaction following a Istocn.

The current calculation of whole core metal water reaction is described in section 9 of BMG-10105, Eev.1, and was reported to be .53%, well below the 1%

limit specified in 10 CER 50.46. The 10 CFR 50.46 rule states that the calculated total amount of hydrogen generated from the chemical reaction of the cladding with water or steam shall not exceed 0.01 times the hypothetical amount that would be generated if all of the metal in the claddin;r cylinders ,

surrounding the fuel, excluding the cladding surrounding the plenum volume, were to react. The additional metal water reaction due to the addition of ,

t

(

zircaloy grids to the core was estimated by conparing the =_w] spacar grid l

surface area to that of the zircaloy cladding. The calculation of the additional metal water reaction due to the presence of the grids was referenced directly to the cladding (i.e., an equivalent amount of cladding oxidation to equal the expected grid oxidation was calculated). The method used for the estimation is outlined below:

1. The wholo core metal water reaction reported in BAW-10105, Rev. 1, was estimated to be proportional to one half of the zircaloy cladding surface area in the hot and 90% bundles. One half of the cladding surface area 1

57 l-l l .

i, - -- .n. -. ,- . . _ , ,. _ . - - . , . . , _ . -, _ _ _ _ . . . _ _ . . . _ . _ . _ _ _ . _ _ _ . _'

~ _ _ . __ _~ _ - _ _ . . _ _ . . _ _ _ . .

' <;t - 4 ,

86-1176204-01 represents a conservative estimata of the surface area whis reaches metal water activation tanparatures (> 1500 F) as substantiated by inspection 1

and extrapolation of the CRAFT core region cladiing tenparatures at the g and of blowdown.

2. '1he additional whole core metal water reaction due to the presence of zircaloy spacer grids is proportional to the exposed zircaloy spacer grid area in the core which reaches metal-water activation tanparatures. 'Ihe i i

fraction of the core whis reached metal water activation tanparatures was determined by adding the 'IHE'I11-B hot pin peak clad tenperatum rise -post blowdown- to the CRAFT claculated end of blowdown core cladding tanparatures.

3. 'Ihe additional metal water reaction due ta zircaloy spacer grids was I estimated by alltiplying the whole core metal water reaction calculated in BPH-10105, Rev.1, (.53 %) by the ratio of the total res.:ted zircaloy apanar grid surface area, to the reacted cladding seurface area.

Ra w upon the methodology previously outlined, it was conearvatively estimated that the whole core metal water reaction would increase .17%, from .53% to

.70%, due to the addition of zircaloy spacer grids. 'Ihe revised value of .70%

is well below the 1% limit specified in 10 CFR 50.46.

• -4. _ , . - - - - , _ ~ e. . ,- , - . . , . - . - - - - - ,we-- , . - - - - . - - , - , , - , . - - - -

I o

o: )

1 86-1176204-01 1.7 CW'rR 6 IDCA LIMI'IS i

'Ihe final IDCA limits reported in this enalysis differ from the interim IOCA j limits implemented for Cycle 6 cperation at the 2, 4, 6, and 8 ft slavations; ]

the linear heat rata at the 2 ft elevation was increased 0.5 kW/ft, whereas the i linear heat ratas at the 4, 6, and 8 ft elevations decreased 1.45 kw/ft, 0.5 kw/ft, and 0.25 kw/ft respectively (Table 4.7-1) . However, the IHR reductions at the 4, 6, and 8 ft elevations were attributed to the implementation of the  !

IHC 07 correlation ard/or the use of the FIECSET reflooding heat transfer coefficients, as diamanad in sections 41 through 4 5. . When the Cycle 6 LOCA p limits were established (9/87), the FIECSET reflooding heat transfer coefficient code had not been approved for IDCA use. 'Ihe IHC OF oorrelation was implemented for the Cycle 7 IDCA limit calculations due to the addition of the MK-BBA fuel assenbly, and was not applicable to Cycle 6 operation in which  :

all fuel assemblies were of the MK-B5 design.

It is concluded that the BOL and extended burnup IDCA limits established for ,

i Cycle 6 operation (i.e., interim IOCA limits) were acceptable. All reductions to those limits have been attributed to the IMC QF oorrelation 'and/or the F2CSET reflood heat transfer ocefficients, both of which are applicable to Cycle 7 operation, ard were not ra:311 red for the establishment of the Cycle 6 LOCA limits.

59

..,.__--..,..,%-. . .-..y .,,,-,.-..,,m,- . - , . . . . _ , , - -

v.-. -.. . _ , - - -. , . - - . . , .

, . *  ?

O-86-1176204-01  :

TABM 44.2-1 CYNF 7 TMA LIMPIS VS CYMF 6 IDC1 LIMITS '

t E2VATIQi (FT) CYCLE 7 LIMTIS CYCIE 6 LIMID 2 16.0 IW/FT 15.5IW/FT 15.75 " 16.8 "

4 16.50 " 17.0 "

6 ,

17.25 " 17.5 "

8 17.00 " 17.0 "

10

, i I

I 1

I 60 p n , . , . . - _ - . . . . - , . ._ - . . , , . . . . - . , - . . , . +- . , _ _ , , _ ,

]

.e O 1 L )

1 86-1176204-01 i l

! .. 5.0 REFDENCES

.1. D.A. Powers ard R.O. Meyer, ClwMing Swelling Models for IDCA Analysis,  !

l NRC Report NURIG-0630, April 1980

2. 43-10105, Revision 1, ECCS Evaluation of B&W's 177-FA Raised-Icop NSS; l 10/89

3. 32-1149241-00 NUREG-0630 177 FA Davis-Basse 2 Fr IDCA Limit; 1/4/84

4. 32-1167963-00177 FA-RL 6 FT IDCA LIMIT; 9/9/87

5. BAW-10143P-A, BWC 00RREIATION OF CRITICAL HFAT FIUX, April 25,1985

6. 32-1138018-00," MARK-BZ EXX5 ANALYSIS;"12/12/82

7. 32-1153287-00,"MK-B/BZ MIXED CORE IDCA LIMIIS," 9/17/84 {

8. RAROD SECO CYCIE 7 REIDAD REPORT, VOIINE 1, MARK BZ FUEL ASSDIBLY REPORT, ,

BAW-1781P, B&W, LYNC20UU, VA. APRIL 1983

9. BAW-1915A , 77-1173653-00, "BOUNDDG ANALYTICAL ASSIESMENT OF NUREG 0630 MXEIS ON IDCA 3Gi/FT LDEIS WIIH USE OF FIECSEr";11/88

10. FLECSET-A OCHPUTER PIOGRAM 'IO CAI!1TIATE HEAT TRANSFER CDEFFICIDTIS DURDG ,

REFIDOD, NPDJIM-3, REV C MARCH 1986

11. K.C. HECK, et al,"FIECKA, Prrvwhnu to Calculate Reflood Heat Transfer >

Coefficients","NPGDsIM-357, hWk & Wilcox, Mart:h 1976

12. B.M. Dunn, et al., "Reflecht Correlation", BAW-10091AP, Appendix B, h W k & Wilcox, August 1974.

13. CRAFT 2- Fortran Ps% sam For Digital Sinulation of a Multinode Reactor Plant During Loss of Coolant, NPGDdIM-287, Rev. A7. 9/87

14. REFIOD3 - Multinode Core Reflooding Ps @ sam, NPGDsIM-519, Rev.11,1/89

15. 'IHE.TAl-B- Ctztputer Code for Nuclear Core 'Ihermal Analysis, NEGD 'IM-405, Rev. P, August 1989 61 I

o o

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86-1176204-01 4

16. TA032 - FUEL PIN PERIMMANCE ANALYSIS, BAW-10141P, BAIKDCK&WIIIDX, LYNQ!!MG, VIR3 INIA, June 1983

17. DB Cycle 6 REIDAD ANALYSIS 32-1169013-00, 9/1/87 ,

18. BAW 10104, REV. 5, Novenbar 1988

19. DB-1 SPECTRM ANALYSIS 32-1175316-00, M.A MA,(Ib Be Released)

20. I.PI/HPI IEDCA ASSGGTIONS 32-1171608-00, 8/7/89

21. TRADE-OFT ANALYSIS FOR TAFY IDL HUSSUR2 023CERN 32-1120819-00,9/15/80 l

22. N. Ime, S. Wong, H.C. Yeh, and L. E. Hochreiter, "PWR FI.ECHT SEASET Unblocked Bundle, Forced Gravity Reflood Task De+:a Evaluation and Analysis Report", NUREG/G-2256 (EPRI NI-2103 or WCAP-9891), November 1981

23. 32-2020-00/01 DR M Spec. Limits, 3/9/77 t

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