ML20214W946

Rev 1 to DPC-NE-1003, Rod Swap Methodology Rept for Startup Physics Testing

ML20214W946
Person / Time
Site:	Mcguire, Catawba, McGuire, 05000000
Issue date:	12/31/1986
From:	Randles J, Tomonto R DUKE POWER CO.
To:
Shared Package
ML20214W932	List: ML20214W928 ML20214W946
References
DPC-NE-1003, TAC-62981, TAC-62982, NUDOCS 8612100472
Download: ML20214W946 (21)

Text

-

. (SAG 46)

McGuire Nuclear Station Catawba Nuclear Station Rod Swap Methodology Report for Startup Physics Testing DPC-NE-1003 REVISION 1 December 1986 J.H. Randles R.J. Tomonto Duke Power Company Design Engineering Department Nuclear Engineering 8612100472 861204 PDR P ADOCK 05000369 PDR

1. Introduction This report describes the calculational procedures used to develop the rod swap constants and describes the measurement procedure used to deter-mine the inferred bank worths. This paper also presents a comparison between the calculated and inferred bank worths for McGuire 1 Cycles 2, 3 and 4, and McGuire 2 Cycles 2 and 3.

In order to perform the " Control Rod Worth Measurement - Rod Swap Test Procedure" (2), the following information must be provided to the station.

This information shall include the bank worths, critical heights and a's.

The critical heights and a's are used to calculate the inferred bank

, worth of each control and shutdown bank, as reduced from information following the iso-reactivity interchange with the reference bank.

This report presents the calculated procedures used to derive these parameters. The calculations as performed in this procedure utilize the approved physics codes and methodologies described in reference (1).

I 4

f i

--- - - - - - - - - - - - - - ~ ~ - ~

2. Definitions The following is a list of the constants needed by the plant, to perform the rod swap procedure. These include:

• [-* Predicted reactivity worth of each control and shutdown bank, when inserted individually into an otherwise unrodded core.

• h -

Predicted critical position of the reference bank after interchange with bank x, starting with the reference bank at 0 steps and bank x fully withdrawn.

• a * -

A correction factor which accounts for the effect of bank x on the partial integral worth of the reference bank, equal to the ratio of the integral worth of the reference bank from h P to the fully withdrawn position with and without x in the core.

In addition, included is a list of constants and their definitions as used in this report.

• W I -

Heasured rod bank worth of bank x from rod exchange

• (g - Measured rod bank worth of reference bank

• (Ap) - The measured integral worth of the reference bank from the measured critical position (h") to the fully withdrawn position.

• h** - The measured critical position of the reference bank after interchange with bank x.

- 3. Measurement Procedure With an initial configuration of all rods out, hot zero power, the integral worth of the reference bank is measured using the standard boration/ dilution technique. The reference bank is the bank that is predicted to have the highest integral worth. All other banks are then "

individually exchanged with the reference bank at constant boron conditions.

J The worth of each bank is then the amount of reactivity change caused by the withdrawal of the reference bank to its new critical height.

The rod bank worth is inferred from the measured reference bank worth and the measured reference bank height using the following equation:

WxI = W" ref

-a x (Ap)x where the above terms are defined in Section 2.0 of this report.

i I

e i

4. Calculational Procedure This calculation is performed using EPRI-NODE-P to model core conditions during the rod swap procedure. The following procedure describes the method of data generation:

1. Calculate the integral bank worth at HZP, ARO critical boron. Insert one bank at a time with no overlap and calculate the bank worth as the difference between ARO and the bank fully inserted condition.

(The calculated highest worth bank will be considered the reference bank.)

2. With the reference bank fully inserted, calculate the critical boron concentration. (The reference bank in boron concentration is used in predicting the predicted rod worth - )

3. Using the above calculated critical boron concentration for the reference bank, the new integral bank worths at HZP are determined.

These values correspond to the predicted worth for each bank ( ).

The reference bank should be inserted in approximately six (6) step increments such that a plot of the integral worth of the reference bank can be obtained. (As should be noted, the K with the ff reference bank inserted, is referred to as the base Kdf) *

4. In order to calculate the critical height, the core is modeled with the measured bank fully inserted. The reference bank is then inserted in approximately six (6) step increments. The critical height (h ) of the reference bank is then calculated by plotting the steps inserted versus K When K equals the base K ff. ff ff, the critical height is found. (This can also be done by linear interpolation between two data points.)

5. In order to calculate a for each bank position, the following expression is used:

Integral Worth of the reference bank from h to the fully withdrawn position with bank x inserted in the core a=

Integral worth of the reference bank fromPh to the fully withdrawn position without bank x inserted in the core i

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

5. Results Table l' presents a comparison between Duke's predicted and inferred bank worths. A review of the available data from McGuire 1 Cycles 2, 3, and 4, and McGuire 2 Cycles 2 and 3, identifies a mean difference of 5.27 pcm or 0.66% between Duke's predicted and inferred bank worths.

Table 2 identifies a comparison between measured and predicted total critical heights. The standard deviation of the differences between the measured critical heights and Duke's calculated critical heights is 12.63.

Table 3 presents some typical a values as calculated for McGuire 1, Cycle 3.

6. Conclusion Reference to the Rod Swap Test Procedure (2) identifies the specific acceptance criteria. In order to satisfy this procedure the following conditions must be met:

(a) The absolute value of the percent difference between the measured and predicted integral worth for the reference bank is 515%.

(b) The absolute value of the percent difference between the sum of the measured and predicted integral worth for all the banks is 510%.

(c) For all RCC banks other than the reference bank, either:

(i) the percent difference between the inferred and predicted worth for each individual bank is 5 30%

EE (ii) lWf-Wl5200pcmforeachbank, whichever is greater.

These criteria were found acceptable using Duke's predicted values.

Based on the predicted and measured data presented in this report the rod swap method described has been verified to be accurate for use in startup physics testing.

,- ,e - -- ......n- - -,--- - - e - -- - --- --- ,n, .~ n- +-- - --- - - - - - - - ---

s J .

j Table 1 Duke Predicted and Inferred Bank Worth *

$ Duke Predicted Duke Inferred Difference

• Difference **

! Unit / Cycle Bank Worth (PCM) Worth (PCM) (PCM) (%)

l 1/2 CA 289 301 -12 -4.0 CB 557 606 -49 -8.1

, CC 786 788 -2 -0.3 j CD 616 566 50 8.8 i

l SA 473 546 -73 -13.4 i SB 443 479 -36 -7.5 SC 370 354 16 4.5 SD 362 374 -12 -3.2

, SE 223 237 -14 -5.9

.]

j Total 4119 4251 -132 -3.1

! Mean - -

-14.67 -3.17 j Standard Deviation - -

35.94 6.80 l

i i

j 1

i I

1 i

Table 1 (Cont.)

Duke Predicted Duke Inferred Difference

• Difference **

Unit / Cycle Bank Worth (PCM) Worth (PCM) (PCM) (%)

1/3 CA 311 305 6 2.0 CB 657 609 48 7.9 CC 789 745 44 5.9 CD 488 466 22 4.7 SA 269 303 -34 -11.2 SB 856 779 77 9.9 SC 394 373 21 5.6 SD 395 383 12 3.1 SE 429 392 37 9.4 Total 4588 4355 233 5.4 Mean - -

25.89 4.14 Standard Deviation - -

31.16 6.34

Table 1 (Cont.)

Duke Predicted Duke Inferred Difference

• Difference **

Unit / Cycle -Bank Worth (PCM) Worth (PCM) (PCM) (%)

1/4 CA 301 313 -12 -3.8 CB 656 677 -21 -3.1 CC 775 778 -3 -0.4 CD 581 556 25 4.5 SA 293 307 -14 -4.6 SB 746 750 -4 -0.5 SC 381 377 4 1.1 SD 382 314 68 21.7 SE 473 471 2 0.4 Total 4588 4543 45 1.0 Mean - -

5 1.7 Standard Deviation - -

27.04 8.0 l

Table 1 (Cont.)

Duke Predicted Duke Inferred Difference

• Difference **

Unit / Cycle Bank Worth (PCM) Worth (PCM) (PCM) (%)

t 2/2 CA 437 459 -22 -4.8 CB 413 452 -39 -8.6 CC 858 871 -13 -1.5 CD 654 664 -10 -1.5 SA 327 430 -103 -24.0 SB 425 480 -55 -11.5 SC 354 375 -21 -5.6 SD 355 374 -19 -5.1 SE 270 292 -22 -7.5 Total 4093 4397 -304 -6.9 Mean - -

-33.78 -7.79 Standard Deviation - -

29.42 6.87

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

. - - . - _ _ ~ -

1 i

{ Table 1 (Cont.)

Duke Predicted Duke Inferred Difference

• Difference ** ,

Unit / Cycle Bank Worth (PCM) Worth (PCM) (PCM) (%)

i 2/3 CA 344 314 30 9.6 I l CB 698 '668 30 4.5 l

• • • CC 869 787 82 10.4 j CD 591 530 61 11.5 i

j SA 381 404 -23 -5.7 i SB 906 842 64 7.6 i SC 438 378 60 15.9 l SD 440 406 34 8.4 j SE 481 424 57 13.4 i

1 1 Total 5148 4753 395 8.3 Mean - -

43.89 8.40 Standard Deviation - -

30.70 6.23 1

4 1

1

• • • This was the reference bank used because vendor supplied data was used for the official rod snap l calculations.

i .

I 1

l

)

1 1

I L

t  !

Table 1 (Cont.)

Evaluation of All Available Data Duke Calculated Difference Differences (PCH) (%)

Mean 5.27 .66 Standard Deviation 40.72 8.69 NOTE:

• Difference = Predicted - Inferred

• • Difference (%) = y W

l .- -

g- y  : ... -

~

3'

,j "'

"1

- a  :,'.

s

/,

L Table 2

'[ * ^

. 4

,+ -

ti ,,

Duke Predicted and ifcisured Critical Heights * '5 "

'i

., s <

'-0i 3x.. p. "., .,4 --

1

\ . . ., ~

4 Critical Height (Steps) , .'s ,

l Unit / Cycle Bank Measured , Predicted ' hDifference (Steps) >

\-, g s - ', , .., - r,., e

'1/2 a' '. ~g 1

~'

, CA 83 A', 88 ..~ -5 .

f . ' s[ ,>6s CB 197 -\ 195 2 4 m --

2 s

CD 183 196 -13 -

i < 4

, r , *.

j r. SA.> v 191 i N '187 ^; '

4 i 4 ,

SB' l .-

' 15b~ ' '\ 157 -

-1 a Y 1 - SC x-144 158' -14 i s

-._ ' SD .'

S 747 156 -9

'T '

' SE i ~

.  % 86' w 92 -6

• 9 s

,s 4 I s

42 _

}

- r Y

jE,of absolute vaiue i

.s i - -

54 , {.

]

s E

, Standard Deviation .

t; 6.63 s4  % 'N - * .

4 +

y 3 f 'k i

's ,'  %' ,

! h e ,

y k \  % > w.

v_. i '

i

./' '_ c

' ._ . 1, .

~

g

+ * \ k

~,.

., 1 r- t ,

~

1

a a -

s, j *%

t s

s 4;

,'y _

! 1 j #  % 4 a T - '

g e em m '%

1 4

i ,

4 6

\.

G 1

i

.,s

.. .s

' ' , n, p'

i ._w -

{ 'llim 'p v-

Table 2 (Cont.)

Critical Height (Steps)

Unit / Cycle Itank Measured Predicted Difference (Steps) 1/3 CA 127 117 10 CB 180 172 8 CC 224 201 23 CD 163 156 7 SA 127 111 16 SC 139 133 6 SD 141 133 8 SE 132 126 6 I - -

84 I of absolute value - -

84 Standard Deviation - -

6.00 i

_ r '

Table 2 (Cont.)

Critical Height (Steps-)

Unit / Cycle Bank Measured Predicted Difference (Steps) 1/4 CA 108 121 -13 CB 201 203 -2 CD 179 191 -12 SA 136 149 -13 SB 218 216 2 SC 147 161 -14 SD 136 161 -25 SE 151 163 -12 I - -

-89 I of absolute value - -

93 Standard Deviation- - -

8.15 I

i l

Table 2 (Coat.)

Critical Height (Steps)

Unit / Cycle Bank Measured Predicted Difference (Steps) 2/2 CA 153 146 7 CB 190 191 -1 CD 202 205 -3 SA 198 186 12 SB 194 183 11 SC 185 182 3 SD 184 182 2 SE 149 141 8 I - -

39 I of absolute value - -

47 Standard Deviation - -

5.49 6

l 4

I

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

1 Table 2 (Cont.)

j Critical Height (Steps)

Unit / Cycle Bank Measured Predicted Difference (Steps) 2/3 .CA 99 112 -13 CB 173 191 -18 CD 158 179 -21 i SA 123 145 -22 SB 228 228 0 SC 130 159 -29 SD 131 159 -28 SE 131 147 -16 I - -

-147

! I of absolute value - -

147 Standard Deviation - -

9.24 i

)

i 1

l 1

I l

l J

1 ,

Table 2 (Cont.)

Evaluation of All Available Data Duke Calculated I (Differences) -155 t I (Absolute Value of Differences) 425 Standard Deviation 12.63 (of the Differences) i 2

4 e

P NOTE:

t

• Difference = Measured - Predicted l I

J i

[ e .

Table 3 O'S Unit / Cycle Bank Calculated 1/3 CA 1.042 CB 0.877 CC 0.870 CD 1.161 SA 1.060 SC 1.052 SD 1.050 SE 0.903 1

l t

l r

I l-

Reference

1. Duke Power Company, " Nuclear Physics Methodology for Reload Design",

DPC-NF-2010A, June 1985.

2. Duke Power Company, McGuire Nuclear Station, " Control Rod Worth Measurement: Rod Swap Test Procedure", PT/0/A/4150/11A, April 1984.

. . . - --- - ~ . -