ML20030A451

Forwards Request for Change to Tech Specs Re Provision for Specific Max Average Planar Linear Heat Generation Rate Limits for Presently Used Fuel Types

ML20030A451
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	06/28/1974
From:	Sewell R, Youngdahl R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	Oleary J US ATOMIC ENERGY COMMISSION (AEC)
References
NUDOCS 8101090536
Download: ML20030A451 (15)

Text

DN Co Fi' Cy.

'~

1 t

$ hg/[

t 3

Consumers C l Po m h

i.s

'x c.

Q %; $.i omc..: m q, upkan Avenue,Jac W, wcedgan mot e Area Code 617 788-05S0

• • • 9""Y 4Q >

n 3' ?. ' ~# 2 rn$

1 fdh June 28, 1974 9

<9 htTM

Mr. John F. O' Leary, Director birectorate of Licensing Re: Docket 50-155 United States Atomic Energy Commission Proposed Technical Specification Washingtor, DC 20545 Change - Amendment to License DPR-6

Dear Mr. O' Leary:

Transmitted herewith are three (3) executed and thirty-seven (37) conformed copies of a request for change to the Technical Specifications of License DPR-6, Docket 50-155 issued to Consumers Power Company on May 1,1964 for the Big Rock Point Plant.

This proposed change is submitted as requested by the Directorate of Licensing staff to provide specific maximum average planer linear heat generation rate limits for the fuel types presently in use at the Big Rock Point Plant. The maximum average planer linear heat generation rate limits specified are as described in our May 30, 1974 letter requesting an exemption from the " Interim Acceptance Criteria for Emergency Core Cooling Systems for Light Water Reactors." This exemption was requested for the period commencing July 1,1974 and ending with the installation of the reactor depressurization system which is expected to be completed by November 1975 This proposed Technical Specification change also contains infomation regarding a minor modification that will be performed at the Big Rock Point Plant during the present outage which will allow continuous feedwater addition following a postulated loss of coolant accident. The addition of this capability results in the design break being the most limiting break size under loss of coolant accident conditions.

In addition, your staff requested further explanation with regard to our use of the maximum average planer linear heat generation rate in the May 30, 1974 letter. A description of our use of the maximum average planer linear heat generation rate is also attached.

Although some of the members of the Plant Review Ccanmittee and Safety Audit and Review Board have participated in the conceptual development of the May 30: 1974 request for exemption and this Technical Specification Change neither the Plant Review Committee or the Safety Audit and Review Board have had an oppertunity to review this Proposed j..

\\

Mr. John F. O' Leary, Director 2

June 28, 1974 Technical Specification Change. These reviews will te completed by July 8,1974 and the results will be transtsitted to the Directorate of Licensing on that date.

Yours very truly, RBS/th Ralph B. Sewell CC: JGKeppler, USAEC

(.,

C0!ESUMERS POWER COMPANY Docket No 50-155 Request for Change to the Technical Specifications License No DPR-6 For the rea:;ons hereinafter set forth, the following changes to the Technical Specifications of License DPR-6 issued to Consumers Power Company on May 1, 19614, for the Big Rock Point Plant, are requested:

I.

Changes:

A.

Change the table contained in Section 5 2.l(b) to read as follows:

d k

,-r

(

Reload E-G and Modified E-G F. J-l & J-2 Reload G Minimum Core Burnout Ratio at Overpower 1 5*

1 5**

Transient Minimum Burnout Ratio in Event of Loss of Recirculation Pumps From Rated Power 15 15 Maximum Heat Flux at Overpower, Btu /h-ft 500,000 395,000 Maximum Steady-State Heat Flux, Btu /h-ft kl0,000 32h,000 Maximun Average Planar Linear Heat Generation Rate at Overpower, kw/ft 13 2 10.8 Maximum Average Planar Linear Heat Generation Rate, Steady State kw/f t 10.6 6.67 Stabi3ity Criterion: Maximum Measured Zero-to-Peak Flux Amplitude, Percent of Average Operating Flux 20 20 Maximum Steady-State Power Level, W 240 240 t

Maximum Value of Average Core Power Density @ 2h0 W, kW/L h6 h6 t

Maximum Reactor Pressure During Power Operation, Psig 1,485 1,h85 Minimum Recirculation Flow Rate, Lb/h (Except During Pump Trip Tests or Natural 6

6 Circulation Tests as Outlined in Section 8) 6 x 10 6 x 10 Maximum Wd/T of Contained Uranium for an Individual Bundle 23,500 23,500 Rate-of-Change-of-Reactor Power During Power Operation:

Control rod withdrawal during power operation shall be such that the average rate-of-change-of-reactor power is less than 50 Wt Per minute when power is less than 120 W, less than 20 Wt Per minute when power is between 120 and t

200 Mg, and 10 My per minute when power is between 200 and 240 MW

• t C.

Delete Figures 5.2 and 5 3 and renumber existing Figures 5 4 through 5.8 as 5.2 through 5.6, respectively. Add new Figure 5 7 attached.

• Based on correlation given in " Design Basis for Critical Heat Flux Condition in Boiling Water Reactors," by J. M. Healzer, J. E. Hench, E. Janssen and S. Levy, September 1966 (APED 5286 ud APED 5286, Part 2).

• • Based on Exxon Nuclear Corporation Synthesized Hench Levy.

S

=

\\

(

B.

Change Table 8-2 to read as follows:

i t

I' TABLE 8,2 EEI UO -Puo '

2 2

and Modified Centermelt E-G Fuels Intermediate Advanced NFS-DA Minimum Core Burnout Ratio at Over-power 1.5*

1 5*

15*

15 Transient Minimum Burnout Ratio in Event of Loss of Recirculation From Rated Power 15 15 15 15 Maximum Hegt Flux at Overpower, 402,000 Btu /h-Ft 500,000 MaximumStgadyStateHeatFlux, Btu /h-Ft 410,000 500,000 500,000 329,000 Maximum Average Planer Linear Heat Generation Rate at Overpower, kW/Pt Maximum Average Planer Linear Heat Generation Rate, Steady State, kW/Ft 10.0 Stability Criterion: Maximum Measured Zero-to-Peak Flux Amplitude, Percent of Average Operating Flux 20 20 Maximum Steady State Power Level, MW 240 240 t

Maximum Value of Average Core Power Operation, Psig 1,485 1,485 Minimum Recirculation Flow Rate, Lb/h (Except During Pump Trip Tests or Natural Circulation Tests as Out-6 6

Lined in Section 8) 6 x 10 6 x 10 Maximum MWD /T of Contained Uranium for an Individual Bundle 23,500 23,500 Number of Bundles:

Bellet UO 1

3 2

Powder UO 1

2

~

2

~

R-te-of-Change-of-Reactor Power During Power Operation:

Control rod withdrawal during power operation shall be such thnt the average rate-of-change-of-reactor power is less than 50 MW Per minute when power is less than t

120 MW, less than 20 MW per minute when power is between 120 and 200 MW P*#

t t

t minute when power is between 200 and 240 MW

• t

• Based upon critical heat flux correlation, APED-5286.

o ONo longer used in reactor.

(

II. Discussion:

By letter dated May 30, 1974, Consumers Power Company requested a variance from the " Interim Acceptance Criteria for Emergency Core Cooling Systems for Light-Water Power Reactors" until the Reactor Depressurization System is operational. The variance request stated that the plant would be operated such that the Maximum Planer Linear Heat Generation Rates would be limited to values that will ensure that peak cladding temperatures under postulated design break accident conditions will not exceed 2300*F. A description of the analysis performed and the results are contained in Appendix A to the May 30, 1974 letter and are incorporated by reference.

Purther analysis has been performed with regard to postulated small and intermediate break sizes. These analyses were performed using the model described in Appendix C to the May 30, 1974 letter and in a manner similar to the Analysis described in Appendix B to the May 30, 1974 letter except that continuous operation of one feed-water pump was assumed until reactor pressure was reduced to 85 psig. At 85 psig the core spray systems provide effective core cooling. The results of this analyses for 9 x 9 fuel are attached in Figure 1 and demonstrate that the design break is the most limiting breaksize from the standpoint of peak clad temperatures.

The 9 x 9 fuel type is the most limiting fuel type in use at Big Rock Point Plant with regard to postulated loss of coolant accidents.

To ensure that an adequate makeup water supply is available to sustain operation of one feed-pump a minor modification is being made. This modification provides a line from the firevater system to the condenser hotwell which can be remotely actuated from the control room. This line is being sized to provide makeup at rate equivalent to the pumping capability of one feed-pump, approximately 1,000 gpm. This capability will be installed prior to start-up from the present refueling outage.

n-

(_

i

~

II. Discussion (Contd)

The modification is being made in as timely a manner as possible.

Suitable motor-operated valves (2) have been located and will likely be obtained fra the Femi I unit. The two (2) valves will be installed in series. The piping run is short and piping presently available at the Big Rock Point Plant will be used.

The water inventory in the condenser hotwell is adequate to sustain several minutes of one feed-pump operation following a postulated break. The feedpump will continue to run in an attempt to maintain steam drum level. Procedures will be developed prior to returning the plant to service that provide operator instruction on initiation of additional makeup from the firewater system and when to secure the feedwater addition and firewater makeup.

The feedpumps at the Big Rock Point Plant can be operated from either of two off-site power supplies. Since the backup off-site power supply was installed in February 1968, only one loss of off-site power has occurred atid that occurred during extremely unusual weather conditions as described in our March 3, 1972 letter to the Directorate of Licensing. There have been four losse of the normal 138 kV power cupply; however, on these four occassions power was automatically transferred to the backup power supply (h6 kv) within three (3) seconds, as designed.

Three of these losses of the 138 kV power supply were momentary due to lightning strikes, while the fourth lasted about one day and was due to a transmission line pole being cut down.

Consumers Power Company By k

m./IO R. C. Youngd

,Sent[rVicePresident Sworn and subscribed to before me this 8th day of June 1974.

l O h t/

Sylvia B. Ball, Notary Public Jackson County, Michigan My commission expires May 18, 1976.

q

w (s

h @d d

m e

2 E

d d

M g

r.,

,l,

, 7...

i 9

g i

.i i,

,I.

I 4 1

I

!'1

'll!

,ill l

.l

., =. =.,.

..a _,. _

y.

et in i..IQ !!d f.i J]V..m i;i

4 4 4

L.'.i i.d.-.li.!.h.

.I.I.:d n.k. ~.

e-.

4 i

.n.

.h 1

?

~

h,..

.. i i. h..U.

.i ".M.

... ;. a:

..+

b' f.'i{l g

F'

'i i j,' fI I Q

H I!

OJ N'

'j E y

'E l;

3 Q..'.

H l tl f I'

1 j j l

.'.d...i...;.E..:...U '

! lW -

6.. ' -......,

i,1 4..H.

..,a

...h.

1.:.l,L e

ts":

n.

i e

, i, p 26

,i i

.e

+

m. l.

e j

g

.i -

8

..g 9

(1

.o o,i g'

s.

G-e.

e 6

.i h(,.1 m.

.q l

l

, ! p.

o \\

i.

i;'. :.

i,,

l9 1

j..

.n.L; f"

.P.

l.i n...I..I..

i, 9..

', J.h lo.

h W

.e J

1 p...

, n.3 8 Ha i~

Li ll ti:

-', "1_Pi i O.

yi ll r"

'h i

I h, H il "l '..

3,'.

f ]d?

l M<f )d

ij:

gi

", i.'!

hI / w*

i

'1 lh:-l 6

'l i

w

.Wl t

,4 q n,,

h o n, 1

• r ni a u.

m a

n n

6 in

i w

i

,o j

g-4 n

O

p L; L '

n a

. }r-l.

., i,'j

.,' n u

.g.n g

p; p n,

i

.4

,oi i

ni q

.t

.l.

l l i!

j ij,' f? j' -

l1,j

. 4'1'

.._ _._.... d.',

.fi l'

l ) ll[,

Ilf.

l.

1 t

ii 1a pi112.

p I"

'^

o ",...

.q

.i. _ _

V._

U.d...z._a. :.h..la m i

3 n.i 3

J

' t h. m Lu.

o m

k.

. A. n z j ::

f.

j o

'q

.a

.,.i c:.

p.

1, i o

n.

m u_

. :. q._.,.

. r,

,,m

_ g... _.

g_ 7_

)

1:

,; Hd h;'

l v

iO

]

(e m

.w -

tL.!

9.._ q, g...

1

a.. a...u

..wz...z;.

.=

a

... v...

5 e

t n I

j.fg"

. _. ~h.

i-0-

l

,5 3.

g.

g" a

Mi

] [U

h,

[.,[,

hk b

[

]

1. 6

.. y 7

. q o

o I

,e.

i dc O_

a i

.c d._i O _O a

"c q

i i

iO g

.g i.d 4

.. h.

g_

.1

..s u

p

.i

.. 7 d

o l u)

Q P l C.s 1 _. '.

,jt i

i 1

. l

.i c:a l.

oc c

.i

n.q.

.)

g.

_...i 3g 3

Ju s

i l

i ec 4

+

3 I

Nh l

,I

V)

I, L

.i i.

.(

l Ii u,,I

.;p o

,g y

l',.

!.H l.'

y, '.. 'h

.. aS H.,N l-I o

o Ii

%l i.

,',,l, 1..,pg u

i i

i b i!'[N '.l

!l I;

i l

NN.

4 i

9 Q

i i

m

.i..

...a i.

4.,.

Cd w

e d

l.

b k'

l i;

y t.

h i

l' I

i G

I s,,

.t..

l I

l CD v

i

.a i

N t..ij j' i

i q

.m

.o

.j

3. i j

.t!

,8,,

i

-O l;.'

'fl tl1

!Il ii

~

.. n O

t I

a j

O

~

,f p

e j

n!!

~[-i; s.

I f

6 i b

k

._. h.._,h k Nbkk 3

1

I s

V MAPLIER I.

Intr duction MAPLHGR stands for Knximum Average Planar Linear Heat Generation Rate.

ItsdimensionsarekW/ft. Given a particular fuel type and a postulated LOCA transient, the peak eled temperature (PCT) experienced by the fuel assembly is strongly dependent on the MAPLHGR value associated with the assembly prior to the LOCA. In order to limit the PCT of any assembly to acceptable values (n 2300*F for the Interim Acceptance Criteria), it may be necessary to limit the MAPLHGR of any assembly during nomal operation.

II.

Definition in Words To explain MAPLHGR, begin with the 4 letters on the right and work to the left:

LHGR=LinearHeatGenerationRate,kW/ft. This quantity is associated with an individual fueled rod.

P = Planar, meaning our attention is concentrated on a particular plane (axial level, horizontal slice, or node) of the assembly.

A = Average, meaning the average LHGR of all rods of the assembly at the plane of interest.

M = Maximum, meaning the largest value of the AFLHGR (Average Planar LHGR) for the assembly is of interest. This value is associated with a unique axial level in the assembly, namely that level at which the assembly axial power peaking occurs.

Using this definition, the MAPLIER for an assembly could be determined from the following procedure:

1.

Start with the knowledge of the LHGR's for each rod of the assembly, as a function of axial coordinate.

2.

Consider the bottom plane (or node).

3 Find the average LHGR of all fuel rods at this plane.

4.

Move up the assembly to the next plane or node and repeat Step 3 5

When all planes have been considered, pick the largest value

b 5

(Contd) of the quantity determined in Step 3 This is MAPLHGR for that assembly.

III. Definition in Core Physics Parameters As one might suspect, there is an equivalent, and easier way of detemining an assembly's MAPLHGR, starting with the total core power and proceeding as described below:

1.

Calculate the " core-averaged AFLHGR" for the assembly of interest. The " core-averaged AFLHGR" is the AFLHGR the assembly would have assuming the power is spatially uniform throughout the core (example calculations follow shortly).

2.

Calculate the " gross peaking" for the assembly of interest by multiplying the assembly (radial) peaking feator by the assembly's axial peaking factor.

3 The MAPLHGR for the assembly is then the product of " core-averaged AFLHGR" and the " gross peaking factor."

For example, c^nsider the calculation of MAPLHGR for an F-type fuel assembly.

This fuel type is a 9 x 9 rod array, with the 4 corner rods being non-fuel cobalt target rods. The " core-averaged APLHGR" is given by the expression P C C 1 2 ARL Where P = Core Power, Megawatts Thermal

= Gama Smearing Factor; ie, the Fraction of Decay Power Released as Heat in the Fueled Rods. The Current Value of Y is 0 96.

Cy = 1,000 kW/W C =12 Inches / Foot 2

A = Number of Assemblies in the Core R = Number of Fueled Rods in the Assembly L u Length of Fueled Portion of the Rods, Inches Thus for full power operation, the " core-averaged AFLHGR" for the F-fuel is:

(2h0MWt)(096)(1,000kW/Mw)(12in/ft)

=6.11kW/ft (84 assemblies)(77 rods / assembly)(70 inches / rod)

The following table swunarizes the quantities for the major fuel types at Big Rock Point:

Fuel Fueled Rod Core-Averaged g

Rods Length, in APLHGR,kW/Ft F

77 70

.6.11 Mod F 76 70 6.19 G

116 70 4.05 G-1 113 68.6 4.25 NES Continuing with the F-fuel example, pick the design assembly radial and axial peaking factors of 1.45 and 1 51, respectively. This makes the gross peaking factor (1.45) (1.51) = 2.19 Expressing MAPLHGR in Sanbols:

F (C C MAPLHGR = F F 7 2 z a g

Where F = Assemblies Axial Peaking Factor F = Assembly (Radial) Peaking Factor a

For This Example, MAPLEGR=(2.19)(6.11kW/ft)=1338kW/ft Note the Following Points:

1.

MAPLHGR is basically a product of core power, radial peaking factor, and axial peaking factor.

2.

MAPLHGR does not involve the local peaking factors of the individual fuel rods. The definition of MAPLEGR was chosen to be independent of the local peaking factors, because the PCT is not very sensitive to the local peaking factors.

The explanation of this behavior is: once the liquid level falls below the plane at which the MAPLHGR occurs, clad heatup begins. Radiant heat transfer becomes the predominant heat transfer mechanism. The heat transferred from a given rod is proportional to the fourth power of the temperature.

This toeans that a small increase in clad temperature of

C.

Y its neighbors because of a higher local peaking factor far that rod produces a marked increase in the heat transferred from that rod.

The increased heat transfer array from the rod tends to slow down "J

the rate of temperature increase, as well as tending to heat up the neighboring rods. In effect, the temperatures in an array of radiant rods tend to equalize because of this " smearing" effect of the radiant heat transfer mechanism. Thus differences in the LHGR of the rods due to local peaking factors do not strongly influence the PCT reached during a LOCA heatup transient.

Typical changes of + 20*F in the FCT can be expected when different local peaking factor sets are used. The paper " Sensitivity Studies of BWR Core Thermal Response to LOCA Using MOXY Code," by D. R.

Evans, presented at the 13th National Heat Transfer Confemnce, AICHE-ASME, August 6,1972, states that a difference of 15'F in the PCT resulted when two different local peaking factor sets were used.

The Oyster Creek Technical Specifications, Docket 50-219,' License DITt-16, Page 310-2 states:

"The peak cladding temperature following a postulated loss-of-coolant accident is primarily a function of the average heat generation rate of all the rods of fuel assembly at any axial location and is only dependent secondarily on the rod to rod power distribution within an assembly. Since expected local variations in pwer distribution within a fuel assembly affect the calculated peak clad temperature by less than + 20*F relative to the peak temperature for a typical fuel design, the limit on the average linear heat generation rate is sufficient to assure that cal-culated temperatures are below the IAC limit."

In general, the change in the local peaking factors with burnup tend to produce increasing PCT's.

At beginning of life, the local peaking factor distribution is more peaked toward the outside rods. In the event of a LOCA, these outer r xis will benefit from radiant heat transfer (cooling) to the cooler cannister, and the PCT, which may occur on ona of these outer

+

e

I, '

k I

rods, is kept somewhat lower than the PCT for the mid-life situation. At end of life, the assembly's inner rods are producing a larger fraction of the assembly power than at beginning of life. In the event cf a LOCA, the inner rods are surrounded by other hot fuel rods, and do not experience direct radiant heat transfer to the cool cannister. The PCT occurs on a rod near the center of the assembly, and is usually higher than the PCT for the mid-life situation.

3. Calculating PCT's as a function of MAPLHGR rather than core power is preferred because the limiting MAPLHGR's (yielding PCT of 2300*F) do not assume any particular values for core power, axial peaking, or radial peaking. The limiting MAPHIGR imposes a restraint only on the product of those quantities.

This provides flexibility for doing LOCA analyses independent of core physics analyses.

l e

ow a

• wa=+=v

~

r

=

V

A'C DISTEIEUTION FOR PART 50 DOCKET ?> &tIAL 4

E i.

(TEMPORARY FORM)

?

CONTROL NO: 5920 FILE:kDDj, FROM:

DATE OF DOC DATE REC'D LTR TWX RPT OTHER Con;umers Power Connany Jcck:on, Mich. 49201 7-1-74 X

Mr. R.B. Sewell 6-28-74 ORIG CC OTHER SENT AEC PDR XXX TO3 g

SENT LOCAL PD2 XXX J.F. O' Leary 3 signed CLASS L7; CLASS PROP INFO INPUT NO CYS REC'D DOCKET NO:

XXX XXX 40 50-155 DESCRIPTION:

ENCLOSU?IS:

-Ltr trans the following.....

Proposed changes to tehh specs.......

(40 cys enc 1 rec'd)

PLANT NAP 2 Big Rock Point FOR ACTION /I' ?C2*ATIC" 7-1-74 JB BUTLER (L)

SCHWENCER (L)

1. ZIEMANN (L)

REGAN (E)

W/ CYS W/ CYS W/7CYS W/ CYS CLARK (L)

STOLZ (L)

DICKER (E)

W/ CYS W/ CYS W/ CYS W/ CYS pany (1) ifAggAtte (L) geleg793 (g)

W/ CYS W/ CYS W/ CYS W/ CYS KNIEL (L)

PURPLE (L)

YOUNGBLOOD (E)

W/ CYS W/ 'CYS W/ CYS W/ CYS INTERNAL DISTRIBUTION FREG FIL TECH REVIEW DENTON LIC ASST A/T IND

?EC HENDRIE GRIMES M IGGS (L)

BRAITMAN v OGC SCHROEDER GAMMILL GEARIN (L)

SALTZMAN

/MUNTZING/ STAFF MACCARY KASTNER GOULBOURNE (L)

B. HURT CASE KNIGHT BALLARD KREUTZER (E)

GLAMBUSSO PAWLICKI SPANGLER LEE (L)

PLANS BOYD SHA0 MAIGRET (L)

MCDONALD MOORE (L)(LWR-2)

STELLO ENVIRO REED (E)

CHAPMAN DEYOUNG (L)(LWR-1)

HGUSTON MULLER SERVICE (L)

1. DUBE w/ input SKOVHOLT (L)

NOVAK DICKER SHEPPARD (L)

1. E. COUPE

/ GOLLER (L)

ROSS KNIGHTON SLATER (E)

/ Schenet:

P. COLLINS IPPOLITO YOUNGBLOOD SMITH (L)

D. THOMPSON (2)

DENISE TEDESCO REGAN TEETS (L)

KLECKER g REC OPR LONG PROJECT MGR WILLIAMS (E)

EISENHUT FILE & REGION (3)

LAINAS WILSON (L)

MORRIS BENAROYA HARLESS STEELE VOLLMER ROOM M MlOlEl3l

1. 1 - LOCAL PDR Charlevoix, Mich.

[] R ll1ll] M l

/ddl EXTERNAL DISTRIBUTION f [][] H g

1. 1 - TIC (ABERNAIHY)

(1)(2)(10)-NATIONAL LABS 1-PDR-SAN /LA/NY

1. 1 - NSIC (BUCHANAN) 1-ASLBP(E/W Bld;;, Rm 529) 1-RR00KHAVEN NAT LAS 1 - ASLB 1-W. PENNINGTON, Rm E-201 GT 1-G. ULRIKSON, ORNL 1 - P. R. DAVIS 1-B&M SWINEBROAD, Rm E-201 GT 1-AGMED (RUTI! GUSSMAN)

1. 16 - ACRS N Sent to Diggs

1. CONSULTANTS Rm B-127 GT 7-1-74 NEWMARK/BLUME/AGBABIAN 1-RD..MUELLER, Rm F-W GT