ML20196D983

Forwards Listed ISFSI Calculation Refs,Per 981110 Telcon

ML20196D983
Person / Time
Site:	Trojan  File:Portland General Electric icon.png
Issue date:	11/24/1998
From:	Quennoz S PORTLAND GENERAL ELECTRIC CO.
To:	Kobetz T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
References
VPN-077-98, VPN-77-98, NUDOCS 9812030008
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Text

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Trojah Nuclear Plant iiricc.-,r n760 Columba River Hwy

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Rainier OR 97048 (503> 556 sn3 November 24,1998 VPN-077-98 Trojan ISFSI Docket 72-017 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Attention: T. J. Kobetz, Project Managu NMSS, SFPO

Dear Sir:

Submittal ofISFSI Calculation References Pursuant to a telephone conversation on November 10,1998, enclosed are the two references requested. Specifically, enclosed are Reference 5.13 of calculation PGE01-10.02.04-04, Revision 4, Neutron Isolator Material, Catalog No. 244, Bulletin S-112N, June 1997, and Reference 5.19 ofcalculation PGE01-10.02.04-03, Revision 7, Spent Nuclear Fuel Effective Thermal Conductivity Report, BBA000000-01717-5705-00010, Rev 00, prepared for U. S. DOE by TRW Environmental Safety Systems, Inc., dated July 11,1996.

If you have any questions regarding this information, please contact Joel Westvold of my staff at (503) 556-6485.

Sincerely,

/

AW l Stephen M. Quennoz 9812o30000 ADOC g j'344 4 Vice President Nuclear y PDR PDn , and Thermal Operations Y

Enclosures c: L. H. Thonus, NRC, NRR R. A. Scarano, NRC Region IV David Stewart-Smith,00E 020043 Connecting People, Power and Possibilities .

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, 3 NEUTRON ISO'LATOR MATERIAL - '. .

- Cataloa No. 244 High Boron -

- High Hydrogen . ~

Non-Flammable ~

Field-Castable -

Inexpensive Catalog No'. 244 Neutron isolator Material is a high baron, high hydrogen, neutron shielding material. The high boron loading makes it especially effec +1ve against

. thermal neutrons. The hydrogen content is approximately 63% th'at of pJre water making it an effective fast neutron shleid as welli The material is completely non-flammable due to its inorganic base, it is field-castable

• oi it can be cast to specific sizes in our factory. Because it is relatively inexpensive it l lends itself to large castings, it is quite strong so it can be cast into thin sections while still maintalning its integrity.

11 has good temperature resistance up to 350 7 (177'C). More than 50% of its.

hydrogen is maintained at this temperature, it will withstand much higher temperatures without altering its mechanical properties. .

i This material can be " cast in the field simply by adding water and mixing. A one cu casting requires 95 lbs of dry-mix (1.53kg is required to cast i liter). It is mixed in a .

ordinary cement mixer and poured into containers without the necessity of heati

. other specialized operations. ~

' Tvolcal Elemental Ar)&s,ig. -

Elemenf Weicht Percent o* 60.01 Al 15.91

~ ca 7.98' .

6.38 S

4.22

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' Density: 112 lbs/cu ft (1.8.gm/ce) .

' Hydr, ogen: 4.2 x 10 'stoma/cc Bor.on: 3,8 x 10 stoma/cc *

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Macroscopic Thermal Neutron Cross Section: E = 2.89cm ~

4 Coefficient of Thermal Conductivity: 5.9 x 10 cal-cm/sec cm* 'C=

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Specific Heat: 0.2 cal /gm 'C Radiation Resistance, gammes: 1 x 10" rads Radiation Resistance, neutrons: 5 x 10" n/cm' .

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i I l SPENTNUCLEAR FUELEFFECTIVE 1 THERMAL CONDUCTIVITY REPORT I

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[ Docamaan Identi6er BBA00000041717-5705610 REV 00 1

1 July 11.1996 1

7,,y_ a for:

U.S. Department of Energy Yucca Mountain Site Characterization Pmject Omce j P.O. Box 98608 Las Vegas,NV 89109 4608 MW W.

TRW Envisnaw=1 Safety Sysiams Inc.

101 Convcotton CenserDdve LasVegas,NV 89109 l UnderContract Number j l Contract #: DE-AC01-91RW00134 j i

! 11/10/98. 15:28 FAI 831 438 5206 SIERRA NUCLEAR -, PGE @ 004 l ,

I Spent Nuclear Fuel E5ective Dennal Conduedvity Report ,

l DI: BBA00000041717-570540010 REV 00 Pese iofxiv l  !

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This technical e-e=+^. 5 pent Naciear Fuel Efective Thermal Conductivity Report, is Wasac l g l Package Developement fiscal year 1996 Deliverable No. ALT 6226.

l l The objective of this report is to describe the development of effective thennal conductivities for

I pressurized waser reactor (PWR) and boiling warer reactor (BWR) spent nuclear fbel (SNF) i as==hl== as a methodology for perfornung future waste package thermal analyses. Finite element j models of various SNF masamhly types with fill envirname=ta of helium, vacuum, nitrogen, and argon have been developed and then used as the basis for the determination of effective thermal

.anductivities of ====hlies with smeared (homogeneous) Ms. Effective thermal eaaanivities are defined here using detailed models of lotact SNF manemhhan evaluated over a l l range of empennnes and heat loads. Effective thermal conductivitim we an ahetame ambodology totheW ; ?@u 2 iia"fortheprochetionofSNFpeakcladdagtemperansas. Qadding -

temperatures desennined using derived effective thermal ca=&iceivities are compend to temperatists j

l using other elaMiar temperanse psodiction methods; and the finite alaamar models and e5ective

thennal conductivities are t=aele==ked against SNF storage cask tests. The discsete SNF asserably l thennel models also provide the trending and thennat behavior of SNF assembhet with a dry fill gas includag the effects of chman I=, water rods, oxidadon rhicarnaen and basket wall gradients. The e5ective thennal conductivities developed here provide a motbod for predicting (with a high level i of confidence) a "best emimase of peak cladding temperatums p SNF ==a =hlies in a dry environment.

! Over-prediction of SNF claddag temperatures due to excessive conservatism can constrain wasee package design and limit the @7 o' posennal waste package design concepts. The analyses

". here indicate that the disciese SNF models me most accurate and sentistic than other

,I i-approaches for pedicting SNF cladding temperatuns. Funbar, the a5emive thannel conductivities, l calcuisand using SNF nadat asults, were found to be primarily a fummion of esapemeure, generally not a ihmetion of assembly heat loed, and suitable for une la predacting best estunate temperatutes l

l of PWR and BWR SNP ====hl= in fill cavironments of helium, vacuum, nimogna, and argon (for at least the center of an SNF container where basket thennal gradients are low). ,

l l The effective thennel eaaawivitics, both the baskemli nesperamme based values and the median l

tempersome based values for use in finise alemaar analyses (FEA), can be applied to SNF coesniners L

i I in a veetacal or horizontal or-ae=*iaa For fill envirnamanes of helium and vacuum, convection in a vertical contamer is miant or aaaaice-at and the effective thennel conductivity rnethod wonki provide a best estimane pndiction of peak claddag temperamres. For buoyant fill gases such as air, j

i nitrogen, or argon, anglecting convection in a venical container (a typical industly pracace) would result in a small conservative bias when using the $ffective thermal conductivity method. Also, for j horizontal amat=inar criaar=rians, contact tow the , SNF assembly and the basket well would tend E

l l no lower peak teenperatures resulting in a best estimate or slightly conservative p r nm l j pe=Acena== when using the effqctive thermal conductivity method.

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DE BBA00000041717-570500010REV00 Paseilof Elv Coopersone The discuse SNF assembly model resuhs were compared to Wooton Epssein conelation temperstme la pr d*=. For each helium fill gas case, the temperamre drop across the assembly was roughly twice that , h by the descrete PWR and BWR SNF models. For till environments of vacuum, nitrogen, and argon the Wooton-Epstein correlataan was seen to be conservative at higher basket l

l wall temperatures, but somewhat nonconservative at lower temperatures (however, at low

! temperatures, SNF cladding temperatures would not be near the design hmits). The WC', ;.l,.

l resuhs are not smprising. lmew, as the correlation was developed for PWR-sl ed assemblies in i air.

l Back check tests of the effective thermal m=Awivities for PEA were perfonned. The results

! showed el-48-- temperatures within 1.5'C of those estimased with the PWR and BWR discrees models (and less than 0.2*C in the heat load and temperamre range of interest for disposal).1he l

PWR and BWR efective thermal maaaivities (for FEA) were also w-r.J to numerical and l experimental studies performed for the TN 24p8"I and REA 2627"I storage casks. For the single assembly comparisons to the TN-24P tests, the discrete PWR SNF model and effective thennal conductivities slightly over-predicted center assembly guide tube temperatures gompared to l

L ,A data seported. While no W=b data was available for peak cladding j temperatures in that test, the discmes PWR SNF model prediceed peak cladding esaperstmes nearly l idsstimi to those predicted by the COBRA-SPS numerical analysis ma&M as part o(the TN-34P I l

i test. For the palf cask haar4= nark of theTN-24P the inclusion of basket nll gradicats around the 4 homosessous mena=hlia (with effective thermal maamivities) ImM 5 senter apsembly and basket temperstavs ibst cloec!y =* hat the -q+' 9 data. However, for lacetions wbsse

basket gradimens won high (amer the ask perunster) the c5ective thennel oceductivity estbod was i sees to under9sedict assembly temperatuna. Finally, for the single assembly comparisons to the

' REA 2023 tests, the BWR cfIgetive thennal conductivities (for PEA) slightly over9sedicasd the cladding temperatue of the BWR assembly center md compared to thennocouple dpta esponed.

Also, the e8ecove themel conductivity teethod prochceed comparabic peak cladding tangierstmes to those paulicted by the HYDRA and COBRA SPS numerical analyses ma&M as part of the l

REA 2023 tests.

For intact P1VR and BWR assemblies, the conductivities derived from the discrete SNF models should provide a best ==ri==ne of SNF cladding tempensums. E5ective thermal conductivities

derived fnxn the PWR SNP models compare quite wen with effective thermal conductivities I developed by General Aramica for the GA 4 caskt8 which were found to be just slightly snore conservative. BWR cffective thennal conductivities .@ for the GA-9 cask,889 however, were 1 found to be significantly -=~vative compared to the discsepe SNP model results and the 1 Wocean-Epseein canelation. Coe should be taken, however. not to extrapolate the effecdve thennat annanivity resuhs to abernate assembly designs (such as manalidaanA maammhlims or asserably sizes i not h ana'lat bem) or aleenume fill gases for which -=ltularia== beve not been complened at this time.

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Spent Nuclear Foc! ENoctive Thermal Melvity Report Paaeillofxiv DE: B'A00000001717-5705 00010 REV 00 nM PWR ENeedvs Therinal Camdectivities Table S-1 sn=marues the recornmaaw bounding PWR effective thenna! conductivity values to be used in conjunction with Equation 6.1-5 for analyses to predict the peak cladding teenperature (based on a known basket wall seinperatune) without enodeling tbs SNF assesubly explicitly.

Table S-2 sununanzes the ===M bounding PWR efective ebennal conductivity values to be used wish finite eleineet (or finite d:Nestace) awlate which explicidy model the SNF anamNy l

as a homogeneous beat sousee.

l Table S-1. Average Effective Caa%!vities for PWR SNF (Basket Wall Based)

Average A Averses L Average ( Average (

Basiet WeR Tasapersese (Whn-K) M/ ark) (W/arQ (W/ ark) 1 in Halumn in Vecman isIt & la Armon l 0.110 I

' 2$*C 0.412 0.1% 0.145 0A51 0.157 0.210 0.195 .

) 50*C 100*C 0340 0.209 0.272 0.257 _

0.643 0.277 0.347 0.326 IS0*C 4

0.762 ON3 0.440 0.417 20P*O 0.898 0A69 0.551 0525 2$0*C 1.053 0.596 OAs2 0.654 300*C 1.224 0.743 0232 0. sos 350*C 400*C IA14 0.914 1A05 0.976 Table S-2. Effective Conductivities for PWR SNF (for FBA) j Asse=Wy K forpsA K.sn PsA K forPEA K.for PEA besten (W/ ark) (W/m K) (Whee (W/ ark) is Niueens b Arnom T_ __ - - is Helium is Vacuum 0.384 01386 0 144 0.127 25*C 0.423 0.107 0.170 0.132

$0*C 0312 0.163 0.132 0.212 100*C 0.616 0.234 0.310 0.288 150*C 0.736 0.324 OA06 0.380 200*C 0.574 0 412 0319 OA91 2$0*C f.028 0.561 0.651 0.622 300*C 1.201 0.711 OA0s 0.774 350*C 0.584 0 973 0.948 400*C 1.392 1

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Figure 5-1. RemmandaA PWR Effective ~Durmal Conductivities I

l Figure S-1 provides a comparison of the m=e~ted PWR effective thermal c@w!vities for each 511 environment opdon. For PWR assemblies, the 14x14 array baiadad the other assembbes l

for helium, and the 17x17 array was WAing for the other fill environments. While the curves for vacuum, nitrogen, and argon are closely spaced, it is obvious that the use of hiium as an SNP

, conrairwr fill gas can signl5cantly reduce peak e!wia: ispawn. Further, the use of a l correlation (such as Wooton-Epssein) developed for aesamhhae in air could limit the design of SNF containers by si airm'ly overgwing SNF cladding %s ; in an SNF container with Mm M p. l Recoenmended BWR Effective Thermal Conductivities For BWR ===amhiw mfra difference was observed Wu MW with the channe.it and assemblies with the channels removed, that separate effective thermal couductivities are provided l for each. Tables S-3 and S.4 (with and without a channel) summmize the re:.:- =M h== ding 8 BWR effective thermal cavi talvity values to be used in conjunction with Equation 6.1-5 for 4 analyses which predict peak cladding Ei-g.c-wr.s based on a known basket kuwem without madaling the SNF menembly explicitly.

1

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Table S-3. Av'erage Effective Conductivities for BWR SNF, with N-1 l

Average k, Average k, Avange k, Average k.

seskatWall Temperenre (w/arQ M/arQ (W/arQ M/urQ in Heinem la Vacaem inNitressa in Arton 1303 0 094 0.125 0.1I8 25'C 0.132 0.110 0.147 0.1%

50*C 0396 0.150 0.192 0.180 100*C 0.202 0.250 0.235 150*C 0.470 0.556 0.278 0.320 0304 200*C 1

0.655 0.348 0A05 0386

250*C l

0.768 OA46 0.505 0AS$

300'C 0.560 0.621 0.602 350*C 0.892 l.032 0492 0.755 0.735 400*C 4

4 4

Table S-4. Average Effective Conductivities for BWR SNF.No Channel I Average k, Average k.

Baekat Wd! Aveinge A Average k.

Tempermare (W/m-Q (W/srA (W/ ark) (W/arQ is Helman in Vacuman _ in N'mosso in Arnon I

0.311 0 lto 0.144 0.134 25*C 0.130 0.166 0.156 50*C 0.344 0419 0.130 0.223 0.210 100*C 3.507 OM 0293 0179 iso-C i 0.611 0327 0.380 0364 700*C 0730 0A29 OA56 0A67 250*C OM7 0.550 0.611 0.591 300*C 0.693 0.756 0.736 350*C 1D21 0.858 0.922 0.902 400*C 1.192 Tables S-5 and S-6 (with and who.t a channel) summarize the &wW bounding BWR effective thermal conductivby vahn, tn 'e used with finite element (or finite difference) methods I which explicitly model the 3NF ft Wely as a horcup.c cous heat source.

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! DI: BBA00000041717 5705-00010 REV 00 Pase vi of xiv Table S-5. FEoctive Conductivities for BWR SNF (for FEA), with Channel f

l m j Assently EforFEA E forFEA EforPEA EforFEA i Meten M/urA N/=rA N/= o M/ ara Temeurasun in Hahams in Vacuss in Nimamme is Armam l

25*C 0290 CA67 0.105, OA94 50*C 0.317 0 061 0.122 0.110 l

! 100*C 0.379 0.121 0.167 0.153 i 0.210

150*C 0455 0 175 0.226 i

} 200*C 0542 0.244 0.299 0.282 250*C 0443 0.328 0.387 0.360 300*C 0.755 0427 0.489 0410 l

l 350*C 0.881 0.542 0 605 0.585 l

l i 400*C 1.019 0673 0.736 0.715 i

Table S4. EKective canawivities for BWR SNP (for PEA), No channet l!

i 1 AssemMy EfarFEA E forFEA E forFEA E for FEA l Median Meurm M/ arc man A M/ arm i Tmusessene inHaMan is Vaceaun in Nimesso in Arman 25*C 0.296 0J062 O.121 0.109 j S0*C 0.327 0.100 0.141 0.129 l

100*C OA00 0.149 0.195 0.181 t30*C OA89 0.217 0.268 0.232 200*C 0.595 0.303 0.spp 0342 l

2s0*C 0.717 OA08 0468 0449 i l

l 300*C 0255 0.533 0.595 0.s75

! 350*C 'I 009 0.676' O.740 0.719 400*C l .T78 0238 0.903 0.882 j Figwas S-2 sad S-3 pmvide comparisont of the sec0emandari BWR c5sceive thennel conductivities

for each ful eavirosament option with and without an 80 mu channel, respectively. For BWR

assemblics, the 9x9 array b0anded the other asscaablics for all of the fill environments. Similar i treeding to the PWR SNF is aboarved for both the channel and no chan=1 cases. Again, the fill

! envimament$ of vacumn, astrogen, and arges are closely grouped with the retuks of the Wo000e-

) Epmeia canelation. Helium, however, provides a much higher c5cetive thennal conductivity, and l therefore would provide significantly lower ^~.,-.Kw in SNF -walans that are filled with ,

} belium.

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BWR mene=hines whhout W H= can be evaluated using the effective therinal aa=*ictivkies for

- hsian wkh chanaala however, this appromeh may be overly conservative for some evaluations. l l l

neverare, the eaaa=a*=vmes for BWR masamhlies both with ned without eh=anals are suponed here.

However, if a "genenc" BWR assembly is the target of a thennel evaluation, k is W that g

. g

the effective thermal ev=dictivities for channeled BWR assemblies be used to be conservative 4 Also, while the diffenst PWR and BWR assembly designs resuhed in minor differences that can be bounded by one assembly anny for each fill environment, results for different fill envimaments l l varied significandy. %erefore, the appmpnate effective thennal eaaAnativity should be chosen for E

use based on the expected fill ges for thennal evaluations of SNF containers.

l l Eval ==*la= G.hi.ai '

i

! The following secouwa-art =enaa= should be followed when using the effective thennel conductivity l i data with finies element codes (see Figue 1.5-1). It should be noted that only even mesh grids l

j (14x14 suggested for PWR assemblies and 10x10 suggested for BWR assemblies) should be used l

when useg the effective thermal conductivity resuks with finha elammar codes. Dis mesh spacing l places a local node at the center of the SNF assembly and will calculate a temperature at this location directly. If an odd spacing is used, the mesh will interpolate this point consistaat with the finite n l

element ==thart The PWR and BWR basket cell widths assumed for these amplyses were l l

1 0.2235 mesess (g.g inches) and 0.1524 meters (6.0 inches), respectively. However, the size of the g

basket opening or the assembly should not affect the ent<mI=riaa oc iavalidene abs effensive thennst

conductivity. De derivation of the effective thermal conducsivity does not skyend on the basket l i width; it is only an average thennel conductivity for the sesion being modeled. Also, inessestag the gap between the SNP assembly and the basket wall should have a minimal effect since the heat l i

'y by radiation; la, , this can be affected by fill gas conductivity. I transfer is y,2-l Generally, for ta==anahle basket designs, the gap size will not have a 4- T-- " impact on the use j

l , of the effective thermal conductivity. When eate M-- the heat load to apply to the SNF mgion, use j j

the cross sectional area or volome of the modeled region (the SNF basket opening), not the area or

vehene of the SNF assembly. Using the SNF assembly area or volume will resuk in a larysr heat l

t load per volume for the modeled region and he e la I=da= win ovw-predict the peak SNFciadding l  !

nempermums.

l Temperatur: 'n' ^ SNF affecsive thennal conductivklas pmvida a ahnple method for l l

calamissing bem -seha==* SNF peak cladding temperatures. De design analyses which contain the calaistariaan prsionned in support of this technical <tari===it are for preliminary design and contain

unqualifiedluncomfinned data and assumptions. These loput data and assumptions will require

' funher confirmation as the weste Packase design pt"'"'" However, the <-hichvines reported here were devanoped in a reproducible calculation with an industry standard code, with limited 3 benchmarks to work previously perfonned within the Civilian Radioactive Waste "- ; - -^ (

System (CRWMS), such that some confidence can be given to these reponod iosults.

I

1 TOTAL P.09

]

_ .