Text

Cycle 4 Core Performance Rept
	ML20155F572
Person / Time
Site:	North Anna
Issue date:	03/31/1986
From:	Iannucci J, Mann B, Snow C; VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	;
Shared Package
ML20155F564	List: ML20155F561; ML20155F572;
References
	VP-NOS-24, NUDOCS 8604220265
	Download: ML20155F572 (49)
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NORTH ANNA UNIT 2, CYCLE 4 CORE PERFORMANCE REPORT I

by J. V. Iannucci I

I I

Reviewed:

Approved:

I M0 %

C.1 La BT D. Mann, Engineer C. T. Snow, Supervisor Nuclear Fuel Operation Nuclear Fuel Operation I

Operations and Maintenance Support Subsection I

Nuclear Operations Department Virginia Electric & Power Company Richmond, Virginia j

l March, 1986

)

1 I

I

I CLASSIFICATION / DISCLAIMER I

The data, techniques, information, and conclusions in this report have been prepared solely for use by the Virginia Electric and Power Company (the Company), and they may not be appropriate for use in situations other than those for which they were specifically prepared.

The Company therefore makes no claim or warranty whatsoever, express or implied,as to their accuracy, usefulness, or applicability. In particular, THE COMPANY MAKES NO WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, NOR SHALL ANY WARRANTY BE DEEMED TO ARISE FROM COURSE OF DEALING OR USAGE OF TRADE, with respect to this report or any of the data, techniques, information, or conclusions in it.

By making this report available, the Company does not authorize its use by others, and any such use is expressly forbidden except with the prior written approval of the Company.

Any such written approval shall itself be deemed to incorporate the disclaimers of liability and disclaimers of warranties provided herein.

In no event shall the Company be liable, under any legal theory whatsoever (whether contract, tort, warranty, or strict or absolute liability), for any property damage, mental or physical injury or death, loss of use of property, or other damage resulting from or arising out of the use, I

authorized or unauthorized, of this report or the data, techniques, information, or conclusions in it.

I I

TABLE OF CONTENTS I

SECTION TITLE PAGE NO.

I Classification / Disclaimer.

...........i List of Tables

. iii List of Figures

............... iv 1

Introduction and Summary.

1 I'

2 Burnup Follow.

.7 3

Reactivity Depletion Follow.

14 4

Power Distribution Follow.

16 5

Primary Coolant Activity Follow.

. 37 6

Conclusions.

. 41 i

7 References...................42 I

I I

I 11

I I

l LIST OF TABLES I

I TABLE TITLE PAGE NO.

I I

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LIST OF FIGURES

(

I FIGURE TITLE PAGE NO.

I 1.1 Core Loading Map.

.4 1.2 Movable Detector and Thermocouple Locations.

.5 1.3 Control Rod Locations.

6 I,

2.1 Core Burnup History

.9 2.2 Monthly Average Load Factors.

10 2.3 Assemblywise Accumulated Burnup: Measured and Predicted.

11 2.4 Assemblyvise Accumulated Burnup: Comparison of Measured and Predicted.

12 2.5 Sub-Batch Burnup Sharing.

I 13 3.1 Critical Boron Concentration versus Burnup - HFP-ARO.

. 15 4.1 Assemblywise Power Distribution - N2-4-07

. 22 4.2 Assemblyvise Power Distribution - N2-4-23

. 23 4.3 Assemblywise Power Distribution - N2-4-38

. 24 l

4.4 Hot Channel Factor Normalized Operating Envelope.

. 25 4.5 Heat Flux Hot Channel Factor, F (Z) - N2-4-07

. 26 4.6 Heat Flux Hot Channel Factor, F (Z) - N2-4-23

. 27 4.7 Heat Flux Hot Channel Factor, F (Z) - N2-4-38

. 28 4.8 Maximum Heat Flux Hot Channel Factor, F *P, vs.

q Axial Position.

29 4.9 Maximum Heat Flux Hot Channel Factor, F, versus Burnup

. 30 q

4.10 Enthalpy Rise Hot Channel Factor, F-DH(N), versus Burnup.

. 31 4.11 Target Delta Flux versus Burnup

. 32 I

I I

i'

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I LIST OF FIGURES CONT'D FIGURE TITLE PAGE NO.

I 4.12 Core Average Axial Power Distribution - N2-4-07

. 33 4.13 Core Average Axial Power Distribution - N2-4-23

. 34 4.14 Core Average Axial Power Distribution - N2-4-38

. 35 4.15 Core Average Axial Peaking Factor, F, versus Burnup.

. 36 g

5.1 Dose Equivalent I-131 versus Time

. 39 I

5.2 I-131/I-133 Activity Ratio versus Time

. 40 I

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1

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Section 1 I

I INTRODUCTION AND

SUMMARY

I On February 20, 1986, North Anna Unit 2 completed Cycle 4.

Since the initial criticality of Cycle 4 on November 2, 1984, the reactor core produced approximately 95 x 10' MBTU (15,934 Megawatt days per metric ton of contained uranium) which has resulted in the generation of approximately 9.2 x 10' KWHR gross (8.7 x 10' KWHR net) if electrical energy.

The purpose of this report is to present an analysis of the core performance for routine operation during Cycle 4.

The physics tests that were performed during the startup of this cycle were covered in the North Anna Unit 2, Cycle 4 Startup Physics Test Report and, therefore, will not 1

be included here.

North Anna Unit 2 was in coastdown from January 23, 1986, at which time I

the burnup was approximately 14,938 MWD /MTU. The coastdown, therefore, accounted for an additional core burn of 996 MWD /MTU from the end of full power reactivity.

I The fourth cycle core consisted of four batches of fuel. The North Anna 2, Cycle 4 core loading map specifying the fuel batch identification, fuel assembly locations, burnable poison locations and source assembly locations is shown in Figure 1.1.

Movable detector locations and thermocouple locations are identified in Figure 1.2.

Control rod locations are shown in Figure 1.3.

I acuti e cor-

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performance indicators.

These are burnup distribution, reactivity I

depletion, power distribution. and primary coolant activity. The core burnup distribution is followed to verify both burnup symmetry and proper batch burnup sharing, thereby ensuring that the fuel held over for the next cycle will be compatible with the new fuel that is inserted.

Reactivity depletion is monitored to detect the existence of any abnormal reactivity behavior, to determine if the core is depleting as designed, and to indicate at what burnup level refueling will be required. Core power distribution follow includes the monitoring of nuclear hot channel 2

factors to verify that they are within the Technical Specifications limits thereby ensuring that adequate margins to linear power density and critical heat flux thermal limits are maintained.

Lastly, as part of normal core follow, the primary coolant activity is monitored to verify that the dose equivalent iodine-131 concentration is within the limits specified by the North Anna Unit 2 Technical Specifications, and to assess the integrity of the fuel.

Each of the four performance indicators is discussed in detail for the North Anna 2, Cycle 4 core in the body of this report. The results are summarized below:

1.

Burnup Follow The burnup tilt (deviation from quadrant symmetry) on the core was no greater than 0.29% with the burnup accumulation in each batch deviating from design prediction by less than 1.8%.

2.

Reactivity Depletion Follow The critical boron concentration, used to monitor reactivity depletion, was consistently within 0.22*. AK/K of the design prediction which is well within the 1*,

AK/K margin allowed by Section 4.1.1.1.2 of the Technical Specifications.

3. Power Distribution Follow - Incore flux maps taken each month indicated that the assemblywise radial power distributions deviated from 2

I I

the design predictions by an average difference of less than 2*..

All hot channel f actors met their respective Technical Specifications limits.

4.

Primary Coolant Activity Follow - The average dose I

equivalent iodine-131 activity level in the primary coolant during Cycle 4

-2 was approximately 2.0 x 10 Ci/gm. This corresponds to 2*. of the I

operating limit for the concentration of radiciodine in the primary coolant.

In addition, the effects of fuel densification were monitored throughout the cycle. No densifiestion effects were observed.

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Figure 1.2 NORTH ANNA UNIT 2 - CYCLE 4 MOVABLE DETECTOR AND I

THERMOCOUPLE LOCATIONS I

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I Figure 1.3 NORTH ANNA UNIT 2 - CYCLE 4 CONTROL ROD LOCATIONS I

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I Shutdown Bank SA 8

SP (Spare Rod Locations) 8 I

I I

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i

I I

Section 2 BURNUP FOLLOW I

The burnup history for the North Anna Unit 2,

Cycle 4 core is graphically depicted in Figure 2.1.

The North Anna 2, Cycle 4 core achieved a burnup of 15,934 WD/MTU. As shown in Figure 2.2, the average load factor for Cycle 4 was 87.6% when referenced to rated thermal power (2775 W(t)).

Radial (X-Y) burnup distribution maps show how the core burnup is shared among the various fuel assemblies, and thereby allow a detailed burnup distribution analysis. The NEkTOTE' computer code is used to calculate these assemblywise burnups. Flo re 2.3 is a radial burnup distribution map in which the assem' lywise burnup accumulation of the core at the end of Cycle 4 operation is given. For comparison purposes, the I.

design values are also given. Figure 2.4 is a radial burnup distribution map in which the percentage difference comparison of measured and predicted assemblywise burnup accumulation at the end of Cycle 4 operation is also given.

As can be seen from this figure, the accumulated assembly burnups were generally within 4% of the predicted values. In addition, deviation from quadrant symmetry in the core throughout the cycle was no greater than 10.29%.

I The burnup sharing on a batch basis is monitored to verify that the is operating as designed and to enable accurate end-of-cycle batch core burnup predic' ions to be made for use in reload fuel design studies.

Batch definitions are given in Figure 1.1. As seen in Figure 2.5, the batch burnup sharing for North Anna Unit 2, Cyclo 4 followed design predictions closely with each batch deviatirig less than 1.8% from design.

E

I I

Symmetric burnup in conjunction with agreement between actual and predicted assemblyvise burnups and batch burnup sharing indicate that the Cycle 4 core did deplete as designed.

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NORTH ANNA UNIT 2 - CYCLE 4 CORE BURNUP HISTORY 17003 16000 p

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G T!MEtMONTHSI CYCLE 4 MAXIMUM DESIGN BURNUP 16600 MWD /MTU

BURNUP HIN00W FOR CYCLE 5 DES!GN -

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0. 29. 8.17. 00 0 26. 561 I

0. 68.l. 0. 44l 12 1 27.321 28.571 19.54l 36.101 19.565 36.118 19.548

.... 2 71..+0. 16. 4.-0. 0.3 8.-0. 86.1..3 7 7 8.-2. 7 71..3 8.31.3 5.961 19.171 29.14 l 2 7. 0 31 l 1 12

.. 24 8...t. 94..l...t. 99. 8. 0. 20. 6 l

13 1 27.071 17.121 18.219 32.84l 18.911 33.248

.l. 0. 06..).-0. 461..+2.3.21.+2. 261..3 941.a l.0.7 4.18.0 31 16. 64 5 2 7.091

===............... Il

........ 3 50.8.-3 271. 0. 121 l AR17Mn(71C AVC i I

1 96.800 29.878 14.391 28.631 1

.I.PC7 01 F F==0. 88.l 14

.... 311. 0. 9.71...I.S.a..l..1. 251. 6.051 29. 281 26.151 14 l 1

.3 S.7 4..1.00. 6.. t 12 8 15 1 $7ANDA80 Otv i l 24.32l 22.164 24.09 I Avc Aes Pc7 1 15

.i....=.1 04.....i

.s. 0. 211. 0. 90.1.-0. 69}

1.O.lFF e......1.29..l I

A P

W M

L E

J H

0 F

E O

C 8

A I

BURNUP SHARING I

(MWD /MTU)

BURNUP TILT l BATCH CYCLE 1 CYCLE 2 CYCLE 3 CYCLE 4 TOTAL hV = +0.02 I

3A3 13997 9255 0

16623 39875 4A2 0

7447 11795 14555 33797 NE = +0.12 I

SA 0

0 17121 13538 30659 6A 0

0 0

18784 18784 SW = 0.15 CORE AVERAGE 15934 SE = -0.09 I

I 12

I I

Figure 2.5 NORTH ANNA UNIT 2 - CYCLE 4 SUB-BATCH BURNUP SHARING SUB-BRTCH 3R3 4R2 SR SR I

SYMBOL GIRMONO SOUR 6E TRI9NGLE STAR 44000 I

I,

40000

. /

7 36000 E

gf S

U 32000 IB

_ /

-/'

A

^'

g

/

r

/

s R 28000

~

I.

g

/

?

[

Y A

m H

8g 24000

-d' f -

/

U

/

. /

20000[

-2 y

p

/

M 16000

/

0, f

M 12000 U

~

8000 j

4000

/

I

[

0-*'

O 2000 4000 6000 8000 10000 12000 14000 16000 CYCLE BURNUP MWO/NTU g

m

I Section 3 I

\\

I REACTIVITY DEPLETION FOLLOW 1

I l

The primary coolant critical boron concentration is monitored for the purposes of following core reactivity and to identify any anomalous reactivity behavior. The FOLLOW

computer code was used to normalize

" actual" critical boron concentration measurements to design conditions taking into consideratior. control rod position, xenon and samarium concentrations, moderator temperature, and power level. The normalized critical boron concentration versus burnup curve for the North Anna 2, Cycle 4 core is shown in Figure 3.1. It can be seen that the measured data typically compare to within 30 ppm of the design prediction. This corresponds to less than i0.22% AK/K which is well within the 1*. AK/K cri'.erion for reactivity anomalies set forth in Section 4.1.1.1.2 of the Technical Specifications.

In conclusion, the trend indicated by the critical boron concentration verifies that the Cycle 4 core depleted as expected without any reactivity anomalies.

II lI

,I I

I 14

I Figure 3.1 NORTH ANNA UNIT 2 - CYCLE 4 I

CRITICAL BORON CONCENTRATION vs. BURNUP (HFP, ARO)

I X

NERSUREO

'RE0!CTED 1800 1600 C

I R

I 1400' T

I R

L 1200,

\\

N O 1000' I

h..

N C

g N

800 I

C

\\

E W

N

^p R

600 R

T I

I 400[

N

E P

3

{

\\

200' I

0-

,I 0

2000 4000 6000 8000 10000 12000 14000 16000 CYCLE BURNUP (MWO/HTUI I

l I

I Section 4 I

POWER DISTRIBUTION FOLLOW I

Analysis of core power distribution data on a routine basis is necessary to verify that the hot channel factors are within the Technical Specifications limits and to ensure that the reactor is operating without any abnormal conditions which could cause an

" uneven" burnup distribution. Three-dimensional core power dis ributions are determined from movable detector flux map measurements using the INCORE' computer program. A summary of all full core flux maps taken since the completion of startup physics testing for North Anna 2, Cycle 4 is given in Table 4.1.

Power distribution maps were generally taken at monthly intervals with additional maps taken as needed.

I Radial (X-Y) core power distributions for a representative series of incore flux maps are given in Figures 4.1 through 4.3. Figure 4.1 shows a power distribution map that was taken early in cycle life. Figure 4.2 shows a power distribution map that was taken near mid-cycle burnup.

Figure 4.3 sbws a map that was taken at the end of Cycle 4 life. The measured re l ai.

ve assembly powers were generally within 4.5*. and the average percent dif ference was equal to 1.9*..

In addition, as indicated by the INCORE tilt factors, the power distributions were essentially symmetric for all cases.

I An important aspect of core power distribution follow is the monitoring of nuclear hot channel f actors. Verification that these f actors are within l

Technical Specifications limits ensures that linear power density and critical heat flux limits will not be violated, thereby providing adequate thermal margins and maintaining fuel cladding integrity. The Cycle 4 Technical Specifications limit on the axially dependent heat flux hot channel factor, F (Z), was 2.20 x K(Z), where K(Z) is the hot channel g

16 I

i factor normalized operating envelope. Figure 4.4 is a plot of the K(Z)

I curve associated with the 2.20 F (Z) limit. The axially dependent heat q

flux hot channel factors, F (Z), for a representative set of flux maps are 9

given in Figures 4.5 through 4.7.

Throughout Cycle 4, tha measured values of F (Z) were within the Technical Specifications limit. A summary of the q

maximum values of axially-dependent heat flux hot channel factors measured during Cycle 4 is given in Figure 4.8.

Figure 4.9 shows the maximum values for the Heat Flux Hot Channel Factor measured during Cycle 4.

As can be seen from the figure, there was an 18.6*4 margin to the limit at the beginning of the cycle, with the margin generally increasing throughout cycle operation.

The value of the enthalpy rise hot channel factor, F-delta H, which is the ratio of the integral of the power along the rod with the highest integrated power to that of the average rod, is routinely followed. The Technical Specifications limit for this parameter is set such that the critical heat flux (DNB) limit will not be violated. Additionally, the F-delta H limit ensures that the value of this parameter used in the LOCA-ECCS analysis is not exceeded during normal operation. For the majority of Cycle 4, the enthalpy rise hot channel factor licit was 1.55 x (1+0.3(1-P)) x (1-RBP(BU)), where P is the fractional power level and RBP(BU) is the burnup dependent rod bow penalty. On October 24, 1985, the Nuclear Regulatory Commission issued Amendment No. 55 to the Operating License for North Anna Power Station and eliminated the rod bow penalty.

Therefore, at the end of Cycle 4,

the F-delta-H limit was 1.55 x (1+0.3(1-P)).

A summary of the maximum values for the Enthalpy Rise Hot Charnel Factor measured during Cycle 4 is given in Figure 4.10.

As can be seen from this figure, the smallest margin to the limit was in the middle of the cycle and was equal to approximately 6.6*..

I 17

The Technical Specifications require that target delta flux

values be determined periodically. The target delta flux is the delta flux which would occur at conditions of full power, all rods out, and equilibrium xenon. Therefore, the delta flux is measured with the core at or near these conditions and the target delta flux is established at this measured point. Since the target delta flux varies as a function of burnup, the target value is updated monthly. Operational delta flux limits are then established about this target value. By maintaining the value of delta flux relatively constant, adverse axial pueer shapes due to xenon redistribution are avoided.

The plot of the target delta flux versus burnup, given in Figure 4.11, I

shows the value of this parameter to have been approximately -2.5% at the beginning of Cycle 4.

After approximately one-third of the cycle, delta flux values had shifted to -4.0% and then moved to -3.5% near the end of Cycle 4.

At the very end of Cycle 4,

the delta flux values rose dramatically to approximately +2.5% due to the coastdown. This power shift can also be observed in the corresponding core average axial power distribution for a representative series of maps given in Figures 4.12 through 4.14.

In Map N2-4-07 (Figure 4.12), taken at 230 WD/MTU, the axial power distribution had a shape peaked slightly toward the bottom of the core with a peaking factor of 1.20.

In Map N2-4-23 (Figure 4.13),

taken at approximately 7,900 WD/MTU, the axial power distribution had become more peaked toward the bottom of the core with an axial peaking factor of 1.16.

Finally, in Map N2-4-38 (Figure 4.14),

taken at approximately 15,250 WD/MTU, the axial peaking factor was 1.11, with a slightly concave axial power distribution. The history of F-Z during the cycle can be seen more clearly in a plot of F-Z versus burnup given in I

Pt-Pb I

Delta Flux = ----- X 100 where Pt = power in top of core (W (t))

2775 Pb = power in bottom of core (W(t))

18

I Figure 4.15.

In conclusion, the North Anna 2, Cycle 4 core performed satisfactorily with power distribution analyses verifying that design predictions were accurate and that the values of the F (Z) and F-delta H hot channel 9

factors were within the limits of the Technical Specifications.

I E.

4 I

I 19 I

W W

W M

M M

M TABLE 8.1 4

NORTH ANNA UNIT 2 - CYCLE to

SUMMARY

OF INCORE FLUX MAPS FOR ROUTINE OPERATION I

I I

I J

1

,1 2 i i

l l

l BURN l l

ll F-O (T) HOT F-DH(N) liOT CORE F(Z)

I is l t

i l UP

.I DANK CHANNEL FACTOR l'

CHNL. FACTOR MAX 31 QPIR 1 AXIAL l' NO.l I MAP DATE l MWD /I PWR' D

I i

' (%)l! STEPS, I

F(XY)l OFF l 0F 1 1

NO.

l MTU I AX1ALll l

1 1

IIAXIAL. i il MAX l i

SET lPolNT F(Z)l 1 MAX l LOC

(%), THIMI

.ASSY PINI POINT F-Q(T)

ASSY l P I N I F-Dif( N )."

BLESI l

l i

__ li 1

1 i

1 l __.

l I _._1 1

l il I

I l

l l

H l 7 1.11-16-841 230a100. 216 P07 l OG 37 1.789 I P071 OG l 1.420 37

'1.20311.49311.0151 NW1 -2.411 16 1 4

18 12-7-8fel It60L1001 228 ll L13 ' kOI 3T 1.723 1 1131 kom 1.375 38 1.19711.475l1.010.

NW1 -2.881 49 l 44 l 9( 5) 12-8-88si 108'a il100 221 l L13 I KO 37

.11.736.I L131 KO 1. 3 784 i 38 11.21011.47311.01841 NW1 -4.301 50 l 113( 6)l12-19-88s1 117011100 206 ! L13 l ko 37 1.780 L131 ko 1.388 1 38 11.20111.875l1.0091 NW1 -3.531 50 l 4

4 116( 7)I 1-8-851 1967 l100 ' 217 l L131 kOI 37 1.733

. L131 kol 1.386 38 11.20111.49011.0011 SWI -3.531 8 8 l 4

i I

I 1.__

l

__. i 11 L

l _ _ l __. _._._

1.

l l

l_I 1

I l

yo NOTES: HOT SPOT L OCAT IONS ARE SPECIF IED HY CIVING ASSIMBLY LOCATIONS ( E.G.

H-8 IS THF CENTER-OF-CORF ASSEMBLY),

FOLLOWED BY lHE TilROUGH R AND IHE [X" COORDINAIE D[SIGNAIEDDENOTED BY THE "Y" COORDINATE WiiH THE SEVENTEEN ROWS OF FUEL RODS PIN LOCATION LETIERID A IN A SIMIL AR MANNER).

IN THE "Z" DIRECT ION Tile CORE IS DIVIDED INTO 61 AXtAL PolNTS STARTING FROM THE TOP OF THE CORE.

( 1). F-Q(T) INCLUDES A TOTAL UNCERTAINTY OF 1.05 X 1.03.

( 2). F-DH(N) INCLUDES A MEASUREMENT UNCERTAINTY OF 1.0f.

4

( 3). F(XY) INCLUDES A TOTAL UNCERTAINTY OF 1.05 X 1.03.

( 4). QPIR - QUADRANT POWER TILT ratio.

( 5). MAPS 10 AND 12 WERE TAKEN FOR INCORE/EXCORE CAllBRATION.

( 6). MAP 11 W.... J,80RTED DURING AQUISITION AND NOT ANALYZED.

( 7). MAPS 14 AND 15 WERE TAKEN FOR INCORE/EXCORE CALIBRATION.

m M

M M

e m

m W

W TABLE I4.1 (CONT.)

l l

h BURN..

F-Q (i) H01 F-DH(N) HOT CORE F(Z) l l

4 l l

l OP BANK CHANNEL FACTOR CHNL. FACTOR MAX l

31 QPTR l AXIAL l NO.

11 MAP

DATE MWD /

PWR D

l F ( XY ) l l OFF OF NO. I MTU

(%)

STEPS l l

l l

lASSY 1 AXlAll l

AXIAL MAX l l SET THIM PINI P0lNilF-Q(T) ' ASSYl PIN; F-DH(N) cPOINT.

F(Z)

MAX LOC : (%)

BLES I

1

_t

__l l

l __I P.1.389 _

38 1.182: 1.483. 1.008

__.NWI -3.15ll 46 l 111 l 2-19-851 3218L100 220 101 Jll 38 1.710 G06 I

118 1 3-21-851 84257 100 224 FOT Jl l 38 1.703 F07 Jll 1.398 38 1.17011.497 11.005 NWL -3.02 48 l 121( 8)l 5-3-851 5:414 1100 221 I LIO Ji 39 1.711 J08 ' Hil 1.413 46

'1.16311.505 11.001 : SW1 -3.79 18 l 4

122 H 6-8 -851 6610 H 100 220 I L10 IJ 8

I6 11.698 I F07 J11 1.418 46 1.158LI.508 l 1. 0084 NEl -3.811 4

16 l 4

123 l 7-8-851 7906'100 222 f051 HI 46 1.710 F07l Jll 1.f422 87.l1.158 1.505 1.0081 NEl -8,101 47 4

4 126( 9)l' 8-9-851 81184 100 ' 226 C06 IJ l 47 1.6T7 F07 Jl.

1.430 47

' 1.139,1. 5 32 )l l. 00 T L NEl -3.05

39 127 9-9-85110083 100 1 228 F051 til ta l 11.689 IO 7, LK,

1. f 22 48 1.14611.506l1.006 NLl -3.66l:

4 85 4

. 28

.110-10-85111?61 1100 ! 228 F05 1 Hil 47

'1.697 TOT;: I kIl 1.828 88 4

88, 1. 18 2. 1.50111.004 ! SE

-3.21 l

4 4

19 4

88 1.787 F11 HI i 1.4?9,

29 110-Pis-85111:46111100 ; 227 fili. Ill i 4

4 1

4

'1.156 ;1.51711.00141 SEi 4

l 32( 10 ) l 11 8511??pis 100 228 009 Hil $2 1.682 I foil LK,'

1.418 53 1. 1843 l1.50911.009 1 NE ' -4.82 ; 42 ll

-3.f:51 46 i33 12-16-85113510 100 228 C06 kl 1 53 1.683 F05;; 111 l 1.801 53 1.150l 1.88911.010L NE

-3.88:

4 83

(

4 4

4 1 38 1-18s-86118 612 100 228 E10 i IJ ' 53 1 1.674 F09; MF.

1.399 53

'1.1581!1.481'1.00611 NE ' -3.551 85 i

4 N

I31(11)I 1-18-86118:736l 100 217 TOS : IJ 53 1.761 F05 I IJ 1.395 53 l1.218 1.8 70 1.0191 NEI

-6.984 40 l 4

138

1-31-86115257 95 228 I F05l HI, 13 1.624

fil, HI 1.f03 12 1.106 1.48511.0101 NE

-0.57 1 39 l 4

139 2-10-86115600 88 228 l. F11 Hil 11 1.699 Fil Hl.

1.805 12 11.14911.89611.0091 NE, 2.591 39 l 4

4 l

I l __ -

l

___ l l

_I l

l l

l ___ ll l

l

( 8). MAPS 19 AND 20 WERE TAKEN FOR INCORE/EXCORE CAllBRATION.

( 9). MAPS 24 AND 25 WERE TAKEN FOR INCORE/EXCORE CAllBRATION.

(10). MAPS 30 AND 31 WERE TAkEN FOR INCORE/EXCORE CAllBRATION.

(11). MAPS 35 AND 36 WERE TAKEN FOR INCORE/EXCORE CAllBRATION.

I I

Figure 4.1 I

NORTH ANNA UNIT 2 - CYCLE 4 ASSEMBLYWISE POWCR DISTRIBUTION N2-4-07 I

1 a

t

..8.=..

m.m

.. 48. 0..?.....

co.sm 1

.44 t

.9CT 91FFEstett.

S.4

5. 5. 3.9

.8CT SIrristsCt.

I

. S.47. 9.71. 4.09. 1.01. 8.99. 9.71. 9.47

. 9.44. 9.74. 1.18. 1.03. 1.11. 0.73. 0.47 t

3.1. S.4. 8.0. 8.9. 1.6. a.8. 0.8.

0.95. 1.10. 1.18. 1.14. 1.89. 1.14. 1.15. 1.18. 0.58.

0.55. 1.19. 1.14. 3.15. 1.29. 1.14. 1.14. 1.10. 9.94 3

0.8. =0.1.

4.4.

0.4. -0. 0..c.S. 8.9. =0.1. *1. 9

. 0.04. 9.95. 4.19.1.21. 3.41. A e t.1.31.1.31.1.19. 0.95. 8.34

. 0.55. 0.94. 1.19. 1.85. 1.85.

3.1.19.1.88.1.14.0.99.0.93.

4 1.4. 0.9 0.7. 1.1.

0.4.

1.

1. 7. 9.8. =0.9. =1.3. *1.6.

9.47. 1.99. 3.14. 1.86. 1.16. 1.14. 5 '

1.14. 3.16. 1.06. 3.18. 5.99. S.47 I

. 0.47 1.11. 3.1a. 1.06. 1.le. 1.39. 1 as 1.19.1.37.I.es.1.17.1.0a.0.47.

S 1.1. 1.1. =4.3. =0.7. =0.4 0.7. e.e. e.S. 6.4. -0.3. -0. 9. =4.4 4.4 0.71.1.18. 4.81.1.17.1.03.1.te.1.e8.1.30.1.03.1.17.1,81.1.1S. 0.71.

. 0.73. 1.te. 1.83. 1.14. 1.03. 1.81. 1.04. 1.31. 4.04. 1.14. 1.19. 1.13. 0.71.

6

. 8.4. 8.7. 1.8. =0.4 S.3. 8.9

0. 9. 0.9 1.4. -4.9. *1.4. *1.5.

0.4 I

. s.44. 1.09. 1.14. 1.11. 1.18. 1.36. 1.08. 1.18. 1.03. 1.29. 1.38. 1.81. 1.34. 1.99. 0.48.

. e.44.1.14 1.19.1.t2.1.17.1.te. 5.04.1.19.1.85.1.84.1.17.1.17. 3.12.1.00. 0.42.

7 4.6. 4.8.

4.4 0.8. 4.4. =0. 5. 1.1. 1.8.

0. 7. 8.6. =4.9.

S.6. *0. 5. *1.4 G.4

. 0.84.1.01.1.te.1.38.1.19.1.06.1.18. 0.9'.1.34.1.06.1.19.1.88.1.89.1.01. s.54

. S.Se.1.04.1.29.1.25 1.81.1.07.1.28. 0.98.1.17.1.95.1.16.1.18.1.17.1.98. 0.56 8

I 4.5.

4.4 4.4. 1.8. 1.5. 1.4 1.3.

0. 7. -0.9. -1.0..t.e. = 5.e. =8.4

0. 7. 3.0.

. e.48.1.09.1.14.1.81.1.18.1.30.1.e4.1.14.1.98.1.89.1.14.1.81.1.14.1.09. 4.48.

. 9.44.1.11.1.12.1.8f.1.30.1.89. 0.99.1.16.1.01.1.18.1.14.1.19.1.13. 1.11. 0.44 9

4.e. 4.4. 4.s. s.S. 1.6. -e.1. -3.5. 4.6.

1. 5.

4. 7.

4. 7. 4.4. -4. 9 1.8. S6.

. 0.71.1.15.1.81.1.17 1.03.1.89.1.08.1.39.1,43.1.17. 3.33. 3.15. e.71.

. 0.79. 1.13. 1.88. 1.19. 1.03. 1.17. 1.84. 1.17. 1.91. 1.15. 1.23. 1.19. 6.73.

as

. *1.0. ~4.8. 9.7. 8.1. 9.1. -4.8. *1. 3..t.8. 1.7. *1.6.

0.9

0. 5. S.8.

. 8.47.1.99.1.14.1.06. 4.16.1.14.1.19.1.18.1.14.1.06.1.14. 4.09. e.47

. 0.47.1.10.1.29.1.00.1.13.1.15. 3.14.1.15.1.15.1.98.1.19.1.3e. 0.47 Il 0.9 0.9 1.3. 4.1. 1.5. 8.8. 4.3..t.8. 4.9.

4. 8. 0.6. e.3.

0. 7.

.......................... =................................... ~....................

. 0.84. 0.93. 1.19. 1.81. 1.41. 1.22. 4.21. 1.81. 3.19. 0.91. 9.94 I

. 9.96. 9.96. 1.81. 1.30. 1.14. 1.19. 1.17. 1.19. 1.17. 0.94. 9.94 18 5.4. 2.9 3.1. 4.8. -4.1. -4.6. -8.8. *1.6. 1.1.

9. 7 8.1.

8.56. 1.14. 1.15. 1.14. 1.89. 1.14. 1.15 1.18. 0.88

. 9.54.1.11.1.13 1.10.1.16.1.le.1.13.1.e4. 9.SS.

IS

. 8.8.

0. 8. *1.6. = 5. 7. = 5. 7. -3.8. -3.1. -1.6. 8.1.

I

. 0.47. 0.71. 1.99. 1.01. 1.09. 0.71. 6.47

. 0.47. 9.75. 1.11. 1.68. 1.06. G.49. G.44.

14

0. 3. 3.4. 1.1.

0. 7. 5.8.

B.4. -3.1.

STafeae8.

. e.44. 4.54. e.48.

..FC7 91FFteteCf.

18 avstaat.

OtvIAfttes

. 9.45. 0.57. 0.45.

.a. nS1 8.7. S.e. B.7.

a.7 I

SUMMARY

I MAP NO: N2-4-07 DATE: 11/16/84 POWER: 100%

1.789 QPTR:

CONTROL ROD POSITIONS:

F.Q(T)

=

D BANK AT 216 STEPS F-DH(N) = 1.420 NW 1.015 I NE O.996

...........l..........

1.203 SW 1.001 i SE 0.988 F(Z)

=

I 1.493 F(XY)

=

230 MWD /MTU A.O = -2.47(%)

BURNUP =

I 22 I

i I

NOB 1H YNNY nNll Z - 3A373 P VSS3WGl AMIS 3 DOM 3W GIS181801lON NI-t-ZE e

e a

m 1

a f

m 9

4 3

0 3

9 9

ea3433&39 ent sneaS

1 seltt3dna

e **1

9 13

e'ot *

ya etdageer33'

G *93

s' tl

e'tI *

na vEW&S *

..........................'9*

19* t t'9 *

d34 STdeleG3B*

' G*ed

0 99

t'et

s'tt

t*et

e 99

s'ed *

e'9 4

S '99

t 'ee

e

63

1

e t

e 9 6

D 'e d

G *t * -t*6 b*0

b*1 * -e'l

1* g. g.g.

8'59 ' 1'09

1'19

1*eS

1* 33

1* eW

t *19

1'09

s'et

1 t

*t*$ * -t'09

1*t1

t'et

1'11

t'ed

t *td

t *e9 *....................'et*

s

e*6e *

0 * **

0 * **

4 * **

t * -9 e*6

e

3 *.1 1.

...............................................'9*

0 69

8 ' 61

t ' tI

1* t d

1' 8 4

1

19

1* 8 4

t 14

t " tt

G

41

e

G* *

e'6*

9'41

1'81

1 14

1 39

t *t*

t

tS

1'ts

1*43

e*61

s'st

e

e*g * -D **

e s

e l

b t

b 9 *.t*d

t*4

e *t..e 1.

9 e.

s'ed

t se

1*t1

t ed

139

t*tS

1*10

t*le

139

1 ed ' t'tt

1*eS

0 04

3

e'99

1'09

t'16

t *09

1*39

1'16

1*TS

t'3e

t tt

f 09

t*88

1*et

0'ed

F*t* I"9

b 9

b 9 * *9 *6

t*S

1'4

3G* 8 *t

t*t

e

E * -e's

4* 4

t '39

1*ed

t*ES

1*eS

l t9

1*04

l te

1'l A

l*19

e 99 *

S '99

t"19

l'td ' t*3d

3

ed

t *tt

1*e9

113

1*10

1'*39

t't9

1* te ' e96

9

e' de

t

t9

f 19

3 *(

8* f

e*t

e'9

9*9

1*6

3*t* te* st* e

f * -t

8 *.t.e = 33.

G **1

l'e1

t'09

1*84

1'19

t'39

1*49

1*34

tw

1*39

1*t9

t *84

1* e9

101

0 *91 *4

s'tt

t'et

t*ed

1'4e

1*t9

1* 3S

1* eS

t'11

1* e6

t *tS

1*t6

t *3 $

1* e9

t'et

s'o,t

1*f

4*3

e b6 eg. t 8A. ge. gt* g*g..t+g e.1.3 *.0 t.

...................'t'..b*f'.....*..*..............g..................................................3.

at

1*13

t *19

T*13

t

e9

t 89

t*eR

t *t9

t

09

1*tt

t 19

1* 32

e*41

s 'tt *

S

st

s'61

t'31

1 19

l'tS ' 1* ed

ltt

t *4S

t

tS

t'ed

1'11

ltI

1*31

0 4$

G e R

9 t*t

4*1

e*4

9*3

s4* t'S. tg. ge.

t9. t.g. pot..g g. 1.3. g.g. 3.g.

S'SR

e*

S'91

t*tI

1*6e

1*34

t'19

1*39

109

1*31

1'09

1*39

1*19

t'34

1*eS

1*e1

s'ot

6

t'ot

e*66

t'et

t

39

1*16

t

39

t *et

t *39 '. t* ed

t

26

t*tS

t* 39

1 00 ' 1'03

s'ot

1+g

.e t = p

t

e*g t*t

eg* e *t *.t* f

g*g

t* g. 1+g.

1 t '...t

4 *

t* f

b *1.

s'99

1'19

1*td

t'39

t'ed

1*39

1*99

t*39

1*ed

1'30

1*td

t*19

s'99

te

s'99

t *tS

1'14

1*tt ' 1*04

1*39

1*e9

t.p'81

1* ed

t '34

1 16

t *td

s'd6 *

-t

t * - t* *. e 3

e*g. 1+t e et*

9.

e t..p g. tag. 1.g - tg.

...................3........1...................................................................

s'ed

t'eS

t'IT

1'04

1*M

t *19

t *19

1 19

1*3S

1*ed

t'31

1'09

s'ed

tt

S'09

t *4S

t *II

t'e6

t 8 4

1 19

1*13

1'19

1'3e

t'ed

t t S

t eo

s'ed *

-e*(

e *t

e '9

l't

0 *9

1 *9

t *S *.1 **

0*e

eg.

t*(.

a t.g.

...............................=.......=......................................e.

8 et

s 61

1*33

1*td

1* 34

1* t9

1*3 4

t *14

1 33

0 61

o et

13

e'te

e'*4$

l'aS

t'14

1* 3#

1*tt

t

39

f *19

1 3T

s'63

e*e,.

9-1**.

g-

.....................'t**t't*al'6**1*4*-S*

3

t * -0

t * -3

..........'9*

8*4*

t 09

1*t9 ' 1 e9

s'go

1* e9

1'19

1* eD

t'33

1'eS

1 13

t'et

0 99

tE 6e

' t'ss *a g g..o e *.g 0. 3't6

1' 9..t.g. 1 g.

t'et

t ts

t *et

l s' d

g

.l-e*g.

1*

6S

t ot

e*99

s *A *

e *ed

e'99

1*et

s'63

S66

s'91

eeS

te

s'ed

e *de

1.e01

e*1 * -e t *.8 t *.t.g.. g 3.............

gg* 8*3 *

....................1 e st

o et -

tanave3 -

te smorse aa.mnee t d

.t

4 *.e 's -

.wd e.tidaman-

e*+s

e'at

e'et

10 1 exE I

SAWWYWA WVd NO: N2-4-2E av13* 1/ 9/9G dom 3W: L00%

L*LLO DdiW:

3ON1801 800 dOSill0NS*

3-011(

=

6 422 NM O*66G l N3 L*009 0 0vNM Y1 222 S13dS 3-OH)N(

=

...........l...........

L*LG9 SM 0*669 l S3 O*666 3)Z(

=

L"GOG 3)XA(

=

L609 WM0/W1n v*0 = -h'L0)%(

9AWNnd

=

I ZC

I i

I I

Figure 4.3 I

i l

NORTH ANNA UNIT 2 - CYCLE 4 ASSEMBLYWISE POWER DISTRIBUTION N2-4-38 F

08ESICTES

. seammes.

. e.44. 0.57. e.44 PW81Cfte.

. e.44. S.38. e.40.

.FCT S!FFleaste..

. 4.1. 1.1.

0. 7.

. peaSENs.

1

.0CT DIFFleepES.

. e.se. 0.71. 8.08. 0 e4. 3.00. 0.F1. 0.9e.

. 0.38. e. Ft. R.83. 0.98. 1.et. 0. F1. 0. 98.

t

. 0.8. 3.4. 0.8. e.4. =0. 6. 92. 0.8.

I 0.57. 8.es.1.16.1.06.1. 25. 8.se.1.16. 8.es. 0.87 8.se.1.e4 3.17.1.07. 8.23. 3.es.1.3 F.1.88. e.Se.

5

. -0. F. =0.8. 0.6. 0.8. -e.1. -4.1. 0.3.

0. 8. -3. 6.

. 0. 56. 0. 98. 1. 21. 1. 34. 1. 27. 1.13. 1. 8 7. 1. 54. 8. 45. 0. 98. e. se.

. e. Se. e 98. 1. 81. R. IS. 1. 8 7. 1.18. 5. 28. 1.1F. 5. 22. 0. 98. 8. M.

4 I.

. -0.1. =0.8. 8.4. 1.2. e.e. 8.4. 4.6. 4.s. e.S. e.0. -4. 0.

. e.80.1.e8.1.25.1.06.1.as.1.18. 8.48.1.18.1.te. 5.06.1.31. l.es. e.se.

. e.49. 3.e4 1.te. 4.es.1.37.1.16. 4.15.1.&F. 4.34. 5.07. 3.81 4.04 0.30.

S

. -8.9. 4. 0. -e.e. -e. F. -e. 8. 4.8. 1.5.

1. F. 3.0. 1.8. -e.4. 4.0. e.6.

. 0.71. 8.16.1.14. 8.38.1.06 1.84.1.05.1.36. 8.M.1.28. 3.36.1.14. 8 Ft.

I

..0.F3.1.17. 1.16.1.8F.1.87.8.39. 1.06.4.50.1.49.1.89.1.84.1.88.e.F1.

6 0.6. e.6 0.8. -0.8. 1.0. 31. 3.8. 2.8. 4.9. S.8. e.e. 4.4. -e.5.

. e.48.1.88. 5.06.1.2F.1.15.1.26.1.es. 8.36. 8.06.1.46.1.18. 3.47.1.06.1.88. 4.44

. S.46. 3.02. 3.06.1.26. 1.E.8.1.27 4.07. 3.39. 1.0F. 3.50.1. 34. 5.24. 1.06. 1.98. 0.46 F

8.8. -e.2. -0.1. -G.e. ~4.8. e.e. 3.4. 8.8. 48.

8. 7. 8.0. -8.8. 4. 8.

-0. 3. 0.6.

I

. 0.57. e.te.1.23.1.13.1.18.1.e4.1.24.1.41.1.26. 4.es.1.10. 4.13.1.23. e to. 0.57

. 4.54. e.96 1.48.1.L5. 5.14.1.es.1.50. 4.04.1.28.1.es. 8.18. 3.1s.1.23. 0.90. 8.8F.

e

-0.5. =e. 5

-4.8.

-0. 0.

0. 8. 3.1.

8. 9. 5.4. 4.8. 1.F.

0. 5. -4. 4. -e.4. =0. 8.

0. F.

. e.44. 8.08.1.06. 4.37.1.18.1.24.1.se.1.36.1.06.1.86. 5.18.1.87.1.06. 5.08. e.45.

. e.44. 0. 99. 1.e4.1.88.1.18. 5.88.1.00.1.36. 1.06. 1.34. 1.18. 3.37. 3.e7. S.es. 0.46.

9

. -3.6. -3. F. 4. 7. 4.3. e.3. -e. 9. -3.4. 0.4 1.6. 1.5.

8. F. 4.1.

0.6. e.8. 8.4 I

. 0.73.1.16.1.14.1.te.1.06.1.86.1.e5.1.86. 8.e6.1.te.1.84. 4.16. 0.71.

. e.69.1.14 1.15. 4.39.1.e4.1.24. 5.06.1.te.1.07.1,29.1.8 7.1.19. 0.F3.

Le

. -4.6. *t.6. -e.9 1.0. 4.3. -3.4

0. 8. 3.1. 1.7. 3.1. 3.4

1. F. 1.7.

. e.se.1.e6. 3.11. 3.06.1.as.1.18.1.14. 3.18. 8.an. 4.06.1.21.1.es. e.Se.

. e.49.1.F4.1.81.1.07.1.25.1.13. 3.M.1.18.1.88.1.00. S.85.1.ee. S.as.

14 I

.-0.4. 4.1.-e.#.

8.0. -S.S. -5.8. -8.5. 5.8.

P.3. 4.e. 1.6. 44. e.e.

. 0.86 e.98.1.31. 4.14. 3.27.1.18.1.27 1.14. 1.21. 0.98. 0.86

. 0. 38. 0. 9%. 1.te. 3.10.1.33.1.09 1.34 1.18. 1. 22. e. 98. 0. 5 7 Et 3.4. 8.8. =0.8. ~B.S. -8 5. -5.8..t. 8. 0.8.

0. F. 5.5.

S. F.

. 0.87. 1.08. 1.14. I.86 1.25. 1.06 3.14. 1.es. 8.37 I

. 0.57. 1.e4.1.14 5.45.

13 e.F. =0 0 4.8. -5.8. 1.28.1.48. 4.14. 1.e4. 0.57 t.8. 4 0. 4.s. e.e.

0. 7

............................................. =......

. e.N. 0.F1.1.88. 0. 96. 8.08. e. F1. 0.55.

. 0.49. e. 71.1.01. 0.95.1.00. 0. 70. e.49 16

. =0 4. 4.s. =0.0. -1.6. 4.0. 4.4. -0.1.

I

. STafsbase.

. 0.4e. 0.87. 0.48.

avg aaet.

15 es.ytaruse

. e.as. e.36. e.44

.FCF e.!FFleE3Ct.

1.e:1

. -e.e...6. -a. 6.

a.s I

SUMMARY

MAP NO: N2-4-38 DATE: 1/31/86 POWER:

95%

CONTROL ROD POSITIONS:

F-Q(T)

1.624 QPTR:

I D BANK AT 228 STEPS F-DH(N) = 1.403 NW 0.999 l NE 1.010

..__.......l.___.......

F(Z)

= 1.106 SW 0.988 l SE 1.003 F(XY)

= 1.485 BURNUP = 15257 MWD /MTU A.O = -0.57(%)

I 24 I

I I

j Figure 4.4 I

HOT CHANNEL FACTOR NORMALIZED OPERATING ENVELOPE 1.2 I

I.0 -

(6.0, 1.0)

(10.91, 0.94)

I 7l I

I "':

(

\\

I

{

\\

g 0.6 I

\\

3 I

0. :

u2.0, 0.45),

i I

01' I

~

I C.0-2 4

6 g

10 12 I

CORE HE10HT IFil TOP I

25 I

I I

NORTH ANNA UNIT 2 - CYCLE 4 HEAT FLUX HOT CHANNEL FACTOR, F (Z)

N2-4-07 I

I a.S.

I.

m I

HCY N

v y

MMMM M

M MM XXXMMMM MMM M M XMMM g

IM M

MM Op M

M M

M U

MMM i.S.

MMMM M

4e M

M N

I M

M z

M g

X o

I XX s

M M

S M

N X

D

=

I

.MM MM d

g h

I E

i I

80TTori OF CORE TOP OF CORE AXIAL POSITION (NODES)

I I

lI 26 I

w-oe-4--

~

,,,m--

m m

I I

s NORTH ANNA UNIT 2 - CYCLE 4 HEAT FLUX HOT CHANNEL FACTOR, F (Z)

I N2-4-23 I

I 2.5.

I%

T s

v I

H Cr b

M NNMMMMM MMM

=

O

+

NXN N

MMM MNNMM M

I M

=.

MM X

X MM MMMM x

M M

xMux k.

1.s.

M MM X

X p.3 X

M E

I X

M E

c M

P

=

M M

_e I

-x g

x D

x d

x I

s 14

=

I l

.1,....;,....;,....;,..

.OTT(M OF CORE TOP OF CORT AXIAL POSITION (NODES)

I l

l I I

27 I

I I

I Figure 4.7 NORTH ANNA UNIT 2 - CYCLE 4 HEAT FLUX HOT CHANNEL FACTOR, F (Z)

N2-4-38 I

I I.

T n

s.e +

v I

i-e Cr

=

2.

e O

ti MMM M

MMX I

4 ga.

1.. +

M M M MMM MMMMM M

MM 4

=

M MM MMMMM MMMMMM N

N N M

M M

MM M M

W I

M MM M

=

M M

M

.M M

G x

=

H

=

M I

M C

1.s +

=

. M h

a M

u.

I H<

k3 0.

+

I I

0.0 +

I..... I.... I.... I..

... I..

,3.,,,,g,,

..I.

.t..

.g..

,g,,,,g,,,g g,, g

=

3.

TOP OF CORT I

AXIAL POSITION (NODES)

I I

I 28 I

i I

Figuro 4.8 NORTH ANNA UNIT 2 - CYCLE 4

)

MAXIMUM HEAT FLUX HOT CHANNEL FACTOR, F0 a P,VS AXIAL POSITION I

F0 s P LIMIT a NRXIMUM F0 s P 2.4 2.2

'N g x g

2.0

)

1-i.,

l

\\

=...

g

..a A

O sh

'i

\\

}.4 F

1.2

.\\

\\

IP 1.0 It I

0.8 1

0.6-t 0.4 I

0.2-I 0. 0-6 55 50 45 40 35 30 25 20 15 10 5

1 AX!AL POS1T10N tN00E1 BOTTOM OF CORE TOP OF CORE 29 I

E NORTH ANNA UNIT 2 - CYCLE 4 MAXIMUM HEAT FLUX HOT CHANNEL FACTOR. F-0 VS. BURNUP

- TECH SPEC LIMIT X MERSURED VALUE 2.4-2.3 iMA 2.2 X

E 'M M

U 2.1 IE H

2.0 A

T F

1.9 L

U IX 1.8 x

O IT E

'q-x v

x

^

C x

x x

x IHR x

N 1.6 N

I!

1. 5 --

F I:

T 1.4-I "0

1.3 I

1.2-s-

0 2000 4000 6000 8000 10000 12000 14000 16000 CYCLE BURNUP (MND/MTUI I

30 I

I WM A 10 NORTH ANNR UNIT 2 - cyggg,

ENTHALPY RISE HOT CHANNEL FACTOR. F-OHtN) VS. BURNUP

- TECH SPEC LIMIT X NEASURED VALUE 1.60 I

i. s 5.;

I E

1.50' F

iT H

R 1 45 IL

~

x y

P Y

X X

X 1.40 x

s S

x x

E H

0 1.35' T-C H

A 1.30' INN E

L 1.25 F

A ICT 0

1.20 RI 1 15 I

I

' " o-0 2000 4000 60C0 8000 10000 12000 14000 16000 CYCLE BURNUP (MWO/MTU1 I

3'

I re., 4. n NORTH ANNA UNIT 2 - CYCLE 4 TARGET DELTR FLUX VS. BURNUP 10 I

8 1

6 I

i R

'G 4

E T

0 a

E 2

I

L F

0 ILU A

X

-2 n

s

^

IP

^

R

-4 C

En T

-6_ 1 E 60b0 14 BOO C

2000 4000 8000 10000 12000 16000 CYCLE BURNUP (MWD /MTU)

I 32 I

I I

Figure 4.12 NORTH ANNA UNIT 2 - CYCLE 4 CORE AVERAGE AXf AL POWER DISTRIBUTION N2-4-07 I

I a.s.

I, F = 1.203 Z

A. O. = -2.47 s.t.

xxxxxx xx,,

xxx x

xx xx I

,,xx x

xxx x

x x

xxx x

x x xx a

x x

I s

m

~

x x

3 x

I g

=

c xx Z

x I

D x

x s

m

=.

x

-x I

=x xx I

I 1.....,

g _ g.

i.-

,....r,....,....

D'cd AXIAL POSITION (NODES) l I

I I

33 I

I I

Figure 4.13 I

NORTH ANNA UNIT 2 - CYCLE 4 l

l CORE AVERAGE AXIAL POWER DISTRIBUTION I

N2-4-23 I

I 1.158 F

=

Z I

A. O. = -4.10 1.2 IN MM MNN NMEN EN EN IEXX I

N X

X N N XX XXXXXX M

N N

EN M

M E

NN M

N N

I M

M I

s is3 g

~

]

M I

]

IM

=

c

_ =

I N

.,M g

NI t

E 5

I 1,.... ;,.... ;,.... ;,...;,....;.. ;

.cf7DPI 0F cwt Ty W Cost AXIAL POSITION (NODES)

I I

I 34 I

I i

J I

Figure 4.14 NORTH ANNA UNIT 2 - CYCLE 4 CORE AVERAGE AXIAL POWER DISTRIBUTION N2-4-38 I

E F

1.106

=

g

/.. o. - -0.57 a.a.

I

=

NNM NNNN M

NNNNN NNMN NN M

M NNNNN NNNMN MM N M M

M N

N N

I N

N N

MN N

N M

S

~

N I

M M

...i E

I

.N N

.a m"

I I

l

,.... ;,.... g....,....,... ;,..

1,...;,..........,.....,.......;

I AXIAL POSITION (NODES)

I I

I 35 I

Figuro 4.15 NORTH ANNA UNIT 2 - CYCLE 4 CORE AVERAGE RXIAL PEAKING FACTOR. F-Z VS. BURNUP I

1.4 I

I I

1.3 A

Ii A

L P

E A

a K

1.2 N

^

G I

e F

6 A

a a

A A

A 3

0 R

o 1.1 I

I I

"~

I 0

2000 4000 6000 8000 10000 12000 14000 16000 CYCLE BURNUP tMWO/MTU1 36 I

r I

I Sectica 5 I

PRIMARY COOLANT ACTIVITY FOLLOW I

I Activity levels of iodine-131 and 133 in the primary coolant are I~

important in core performance follow analysis because they are used as indicators of defective - fuel. Additionally, they are important with respect to the offsite dose calculation values associated with accident analyses. Both I-131 and I-133 can leak into the primary coolant system throught a breach in the cladding. As indicated in the North Anna 2 Technical Specifications, the dose equivalent I-131 concentration in the primary coolant was limited to 1.0 pCi/gm for normal steady state operation.

Figure 5.1 shows the dose equivalent I-131 activity level history for the North Anna 2, Cycle 4 core. The demineralizer flow rate averaged 75.7 gpm during power operation. The data shows that during Cycle 4, the core operated substantially below the 1.0 pCi/gm limit during steady state operation. Specifically, the average dose equivalent I-131

-2 concentration of 2.0 x 10 pCi/gm is equal to 2*. of the Technical Specifications limit.

The step increase in coolant activity in July, 1985, was due to the recalibration of the germanium-lithium detector that is used to count the coolant samples. The change in the coolant activity measurements was not caured by fuel cladding defect formation.

The ratio of the specific activities of I-131 to I-133 is used to characterize the type of fuel failure which may have occurred in the g

3,

I I

reactor core. Use of the ratio for this determination is feasible because I-133 has a short half-life (approximately 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br />) compared to that of I-131 (approximately eight days).

For pinhole defects, where the diffusion time through the defect is on the order of days, the I-133 decays leaving the I-131 dominant in activity, thereby causing the ratio to be 0.5 or more. In the case of large leaks and " tramp"* material, where the diffusion mechanism is negligible, the I-131/I-133 ratio will generally be less than 0.1.

Figure 5.2 shows the I-131/I-133 ratio data for the North Anna 2, Cycle 4 core at a general average value of 0.09.

The.se data indicate that there were probably no defects in the fuel used during Cycle 4, but tramp material remained from the previous cycle during which fuel defects were present.

I I

I

. r -, _ si-s e f1ss1 - b1. -.r1a1 whi e aeher.s m e. - s14. -

the fuel.

38

I I

I Figure 5.1 NORTH ANNA UNIT 2 - CYCLE 4 DOSE EQUlVALENT l-131 vs. TIME TECHNICAL SPECIF ICATIONS LIMIT I

I W

e I-s O

O e

g 2

e O

sh **1pefAMe*

e I

a s, oe ac, s

w o

g, e's e

e e

e u

o o

e I

O O

e 0

f u-

~o e

o r-

~

0" I

O e

e o

.100 t

j y l

r' i-y 1

i N

I l

.50 g 2

o I

DEC JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FES 1985 1986 39 I

Figure 5.2 NORTH ANNA UNIT 2 - CYCLE 4 1-131 / l-133 ACTIVITY RATIO vs. TIME s

I

=

I O

I-s I

Ed e

_~

>o I

Ea I

f S

\\

O e

To e

e I

~

e Cl I

e o

e e

g a

a 6

e c peps &

iv(e pn 4M a N etwaveWM

.I a

e C

F I-

" {

l-1 1

~

-y

==

l

.so m lI l

\\

l 5

,0 DEC JAN FEB bAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB I

1985 1986 40

I Section 6 I

l CONCLUSIONS i

I The North !.nna 2, Cycle It core has completed operation. Throughout this cycle, all core performance indicators compared favorably with the design I,

predictions a d the core related Technical Specifications limits were met with significant margin. No significant abnormalities in reactivity or burnup accumulation were detected. In addition, the mechanical integrity of the fuel has not changed significantly throughout Cycle 4 as indicated by the radioiodine analysis.

I

/

I I

lI 41

Section 7 I

REFERENCES 1)

B. D. Mann, " North Anna Unit 2, Cycle 4 Startup Physics Test Report," VEP-NOS-14, November, 1984 I

2) North Anna Power Station Unit 2 Technical Specifications, Sections 3/4.1 and 3/4.2.

I, T. K. Ross, "NEWTOTE Code", VEPCO NFO-CCR-6, Rev. 8, April, 1981.

3) 4)

R. D. Klatt, W. D. Leggett, III, and L. D. Eisenhart,

" FOLLOW Code," WCAP-7482, February, 1970.

5)

W. D. Leggett, III and L. D. Eisenhart, "INCORE Code,"

WCAP-7149, December, 1967.

II l

l I

I 42

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