Swamping Effects on Tritium Permeation in Solid Breeder Blanket Units

Transcription

1 Swampig Effecs o riium Permeaio i Solid Breeder Blake Uis Preseed by We Guo Wih oribuios from A. Yig, M. J. Ni, M. Abdou BBI- Nov. - ec., 5, Saa Barbara BBI

2 Oulie Review: effecs of covecio o riium permeaio i solid breeder blake uis Swampig Effecs o riium permeaio aabase Uceraiies Experimeal Pla BBI

3 Review riium permeaio io he FW coola by implaaio ca be egleced wih a Beryllium proecive layer. riium permeaio from blake o helium coola should be corolled J /J <.5%. o develop a predicive capabiliy for riium permeaio compuaio (J ) which accous for flow, uclear heaig, ad riium producio profiles - Velociy profile -ovecio ad coducio of hea -ovecio ad diffusio of riium -Isoope swampig effec -omplex geomery BBI

4 BBI 4 FEMLAB-based Muli-physics Mahemaical Models Purge gas flow * * K p u u u u u μ ϕ μ ρ ρ = + ]} ) / / ( exp[ { * * d p y w N + = ϕ ϕ ]} ) / / ( exp[ { * * d p y w N K K + = ), ( X Q p p + = + λ ρ ρ u ), ( X Q s p + = λ ρ p p = + λ ρ ρ U c b a He oola Srucure Breeder zoe x z y ovecio ad coducio

5 BBI 5 Mass Balace ad Boudary codiios = = A he symmery A he oule boudary riium mass balace ), ( X Q c + = + u = = + U Purge gas Srucure He-coola Boudary codiios / KP = = / KP = = A purge/srucure ierface A srucure/oola ierface

6 Effecs of ovecio =67K.6 =67 K riium Parial Pressure (Pa) 4 v=. m/s No permeario riium Parial Pressure (Pa) v=. m/s No permeaio X(m) X(m) BBI 6

7 Isoope Swampig effec due o he Addiioal Hydroge If o hydroge addiio o he purge sream, he probable riium species are ad O, while O is assumed o o permeae hrough he coola. he riium permeaio rae is / J = KP / If some amou of hydroge is added o he purge gas, isoope effecs should be cosidered. riium permeaio rae will be reduced K is he permeabiliy ad k is he equilibrium cosa / / J = KP k P H / H Referece [] riium Permeaio hrough Seam Geeraor Maerials [] riium Percolaio, ovecio, ad Permeaio i Fusio Solid-Breeder Blake BBI 7

8 Surface coceraio If he molecule is homouclear: Whe solue aoms i surface approach equilibrium wih he gas mixure, he / Sievers law will be applied. = K If he molecules are heerouclear: he reacio ca o be i equilibrium uless he homouclear molecular species exis i he correc proporios for he aomic species coceraio i he surface. For diaomic gas molecules composed of differe aomic species i ad j, he surface coceraio is i = K sij Pmij s s P m BBI 8

9 Isoope Swampig =67K v=. m/s Effec (/k / =/8) =67K v=.m/s.5 rium Parial Pressure (Pa).5 Wih Hydroge No Hygroge No Permeaio riium Parial Pressure (Pa) 4 Wih Hydroge No Hydroge No Permeaio X(m) J /J over a purge gas flow pah of m X(m) Wihou H Wih wppm H = 67 K.%.7% = 77K 8.8%.76% BBI 9

10 Equilibrium osa J = KP H /k / P / H wppm H U =.m/s = 67K /k / J /J Oule P P /.4%.56.9 /8.7%.56. /.89%.558. /5.498% /5.588% %.55.7 BBI

11 Summary able: wihou/wih H (wppm) Wih H Wih o H Ile v J /J Oule P Oule P (No-Perm) P J /J Oule P Oule P (No Perm) P =67K. m/s.84% % m/s.7% % m/s.55% m/s.8% m/s.475% =77K. m/s.% % m/s.76% % m/s.47% % m/s 4.49% m/s.7% he permeaio rae is high ad uaccepable wihou akig io accou isoope swampig effec or usig permeaio barrier. BBI

12 H Isoopes iffusiviy/permeabiliy Measureme.Experimeal mehod.heory of sigle layer permeaio Pp / Pp / Q( ) = J ( ' ) d' = d 6.Isoope depedece / d Pp d π = ( ) / = ( m / m ) / K = + s p J ( ) ( ) d = π exp d π exp d Schemaic of permeaio apparaus BBI

13 Available experimeal resuls F8H drivig pressure - 5 Pa emperaure 7-74 K Permeabiliy ( mol m s - Pa -/ ) =.9-8 exp( -47/R) iffusiviy (m s - ) =.7-7 exp( -95/R) Siever s cosa ( mol m - s - Pa -/ ) =.77exp( -688/R) Eurofer 97 compared wih F8H Permeabiliy iffusiviy BBI

14 Uceraiy i he aabase A high pressure, he permeaio is diffusio limied(j~p.5 ). A he lower emperaure ad pressure, he pressure depedece of J is seeper ( J~P a ) a>.5 because of surface ifluece o he permeaio. herefore experimeal assessme is eeded for accurae predicio of riium permeaio. Usig he exisig daa, if Siever s law applied, riium coceraio i he srucure side is higher ha i he purge gas side. he riium pressure is < Pa i HB BM (or solid breeder purge gas codiios, ec). he rage of exisig correlaios based o experimeal daa a high pressure rage..5 s = KP m s = KP m... X X (m).5 BBI.8 4 Y (m)

15 Fuure Experime Pla Verify he hydroge isoope diffusiviy, permeabiliy, solubiliy i he srucure i he low pressure rage ( P<Pa) Measure he riium permeaio wih helium purge gas. -Sigle effec: emperaure is uiform -Muli-effec: emperaure profile, velociy profile, riium buildup, isoope effec ec. BBI 5

16 Sigle effec experime Heaer orol Sysem esig pipe Measurig pipe Mass Flow oroller Mass Flow oroller Vacuum Sysem Mass Specromeer Mass Specromeer He Exaus sysem BBI 6

17 Summary ad oclusio Wih addiioal H exiss i he purge gas, he riium permeaio will be highly reduced. Exisig daa for riium permeabiliy, diffusiviy, solubiliy are for he high pressure rage. A low pressure rage, he surface codiio, he permeaio mechaism will affec riium permeaio. Fuure experime o permeaio measureme wih helium purge gas. BBI 7