Atucha-2 PHWR Three Dimensional Neutron Kinetics Coupled Thermal-hydraulics Modelling and Analyses

8/17/2019 Atucha-2 PHWR Three Dimensional Neutron Kinetics Coupled Thermal-hydraulics Modelling and Analyses

1/49

UNIVERSITÀ DI PISAUNIVERSITÀ DI PISADIPARTIMENTO DI INGEGNERIA MECCANICA,DIPARTIMENTO DI INGEGNERIA MECCANICA,

NUCLEARE E DELLA PRODUZIONENUCLEARE E DELLA PRODUZIONEVIA DIOTISALVI 2, 56100 PISAVIA DIOTISALVI 2, 56100 PISA

G r u p p o R i c e

r c a N u c l e a r e

S .

P i e r o a

G r u p p o R i c e

r c a N u c l e a r e

S .

P i e r o a

G r a d o

G r a d o

Atucha-2 PHWR threeAtucha-2 PHWR three

dimensional neutron kineticsdimensional neutron kinetics

coupled thermal-hydraulicscoupled thermal-hydraulics

modelling and analyses by themodelling and analyses by theRELAP5-3!RELAP5-3!

"# Parisi$"# Parisi$ A# el %e&o$A# el %e&o$ '# (a))antini$ *#'# (a))antini$ *#

+Auria$ ,# &ano&+Auria$ ,# &ano&

RELAP5-3 .ser /eminardaho .ni&ersity "ampus$ daho *alls$ ./A

01-2 %o&ember 21


2/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &

G r u p p o R i c e r c a N u c l e a r e S .

P i e r o a


P i e r o a

G r a d o

G r a d o

Outline Introduction

Atucha II PHWR Features

280 channels TH model

HELIOS CrossSections Li!raries

"# $% TH model

Sam&le results

Conclusions


3/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3


P i e r o a


P i e r o a

G r a d o

G r a d o

Introduction Ar'entinean electric utilit( )$ucleoelectrica

Ar'entina * Societad Anonima+ ,$ASA- si'ned ana'reement .ith the San Piero a /rado $uclearResearch /rou& ,/R$SP/- o the 1niersit( o Pisa ,1$IPI- in 2003 or the deelo&ment o adancedsimulation models or the AtuchaII $PP

/R$SP/41$IPI deelo&ed hermal-hydraulics5%eutronics5 "* and /tructural (echanics models or the saet( anal(sis o the &lant

Currentl( /R$SP/41$IPI is also assistin' $ASA inthe deelo&ment o the "hapter 05 o the */AR

6estEstimate Plus 1ncertaint( ,6EP1- method&ursued or licensin' calculation deelo&ment o a6E RELAP7"# model or licensin' anal(ses


4/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% (


P i e r o a


P i e r o a

G r a d o

G r a d o

Atucha II PHWR Features AtuchaII is a 92 :We Siemens desi'ned PHWR under construction in

Lima5 Ar'entina

Constructions started in ;98;5 sus&ended in ;99<

Constructions resumed in 20075 =rst criticalit( scheduled or 20;0

Hea( .ater cooled5 hea( .ater moderated PWR

1ni>ue eatures?

Primar( circuit !ased on the %onoiPWR desi'n Circuit or moderator coolin' 4 FW &reheatin'

$atural 1ranium uel

@ertical Fuel Channels

Lar'e RP@ ,3" meter internal diam-


5/49



P i e r o a


P i e r o a

G r a d o

G r a d o

Atucha II PHWR Features Primar( circuit characteristics B con='uration

2 1Tu!es S/5 2 :CP

Primar( side &ressure? ;;7 :Pa

Primar( side tem&eratures? 238 C at RP@ inlet5 ";""C at RP@ outlet

Total thermal &o.er transerred to the steam .ater c(cle ? 2;3< :W

Aera'e :oderator Tem&erature? ;30 C

< 1Tu!es HD or :oderator coolin' 4 FW &reheatin'

(oderator "ooling"ircuit

Primary "ircuit


6/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% )


P i e r o a

G r u p p o R

i c e r c a N u c l e a r e S .

P i e r o a

G r a d o

G r a d o

Atucha II PHWR Features Fuel &laced in ue CRs

"R layout

*uel Element

RP4 Layout


7/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% *


P i e r o a

G r u p p o R


P i e r o a

G r a d o

G r a d o

Atucha II PHWR Features Emer'enc( 6oron Inection S(stem desi'ned to act durin' RIA ,e'5

L6LOCA-

To counteract &ositie reactiit( ecursion due to the reactor &ositie oidcoeGcient

< Lances inect hi'h &ressure solution o !oric acid into the moderatortan

S(stem reaction time reduced !( $ASA to rou'hl( 07 secs

oronn6ection

Lance 70 o8 9:


8/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% %


P i e r o a

G r u p p o R


P i e r o a

G r a d o

G r a d o

Rationale for the Nodalization

Structure $odaliation is the result o a !rainstormin' &rocess .here thecom&utational resources aaila!le and the e&erience o the user&la( a maor role consistentl( .ith the o!ecties o the anal(ses

Selected code .as RELAP7"#J deelo&ed or industrial

a&&lications in 1S5 inde&endent rom the code,s- used !( the

re'ulator

%e( role o?

:aimum allo.ed num!er o nodes5

:aimum alloca!le com&utercode memor(

T(&icalit( o the accident scenarios to !e anal(ed

DEGB LBLOCA – Initial Reactivity Excursion and Recovery

LBLOCA and other transients

1ser in su&&l(in' unaaila!le inormation

Proidin' suita!le >uali=cation


9/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% +


P i e r o a

G r u p p o R


P i e r o a

G r a d o

G r a d o

Rationale for the Nodalization

Structure )280 channels nodaliation+ consistent .ith thet(&icalit( o the accident scenarios to !e anal(ed,e' #E/6 L6LOCA * Initial Reactiit( Ecursionand Recoer(-

Com&uter resources not suGcient to im&lement allC$A2 ECCS and Lo'ics

)0 channels nodaliation+ consistent .ith thet(&icalit( o the accident scenario ,e' L6LOCAand other transients-

Code com&uter resources saturated !(

im&lementation o suita!le ECCS and Lo'ics5 so? )280 channels nodaliation+ or "# $% * TH anal(ses

)0 channels nodaliation+ or 0# $% * TH anal(ses


10/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $'


P i e r o a

G r u p p o R


P i e r o a

G r a d o

G r a d o

50°

CL axisHL axis

CL !L

CL"!L"

DC Nodalization & RPV Syetry

Due to the le#s #eo$etry not all the

coolant co$in# %ro$ a loo& exits %ro$

the sa$e loo&' A $ixin# ()et*een

inlet and outlet+ has to )e ta,en into

account


11/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $$


P i e r o a

G r u p p o R

i c e r c a N u c l e

a r e S .

P i e r o a

G r a d o

G r a d o

DC Nodalization !Hydraulics"

- vertical (do*n*ard oriented+ &i&es

axially su)divided in "5 volu$es

.oined )y cross/%lo* ($ulti&le+ .unctions

(co$&onent no' in the le%t %i#ure+

- )ranches re&resent the u&&er &art1 t*o

o% the$ lin,ed to the CL

DC/23 )y&ass connection


12/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $&


P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

#P Nodalization

4hree layers

+ Botto$ &art – hori6ontally oriented (red+ Level/ (L+

"+ Botto$ &art u& to the channel inlet – vertically oriented (#reen+ Level/" (L"+

7+ Channel inlet u& to the lo*er %ace o% core &late – vertically oriented ()lue+

Level/7 (L7+


13/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $3


P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

#P Nodalization

L3 #rid nodali6ation a&&roach

8ive rin#s are identi%ied containin# an

9entire: nu$)er o% )oxes

"

7

;

5Withouth!""#$ i"$#t%&

CL1 'L1

CL2'L2


14/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $(

G r u p p o R


P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

#P NodalizationL3 #rid nodali6ation a&&roach

7- sectors (a$&litude o% each sector is

0° < =$axi$u$ co$$on divisor> %or

?0°1 ;0° and 50°+ divide the )oxes into

"00 &arts (su)/)ox+ re&resented )y

"00 9)ranches:


15/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $5

G r u p p o R


P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

#P NodalizationBottom partBottom part

5 radial rin#s (accordin# to L3 &late su)division+

- a6i$uthal &arts (accordin# to DC su)division+

"5 hori6ontal 9)ranches: constitutethe )otto$ L3

4he external rin# is connected to

DC &i&es (#reen circles+

Each hor' )ranch is connected to

the vert' )ranches %or$in# the L3

#rid (red circles+


16/49RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $)

G r u p p o R


P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Core channels Nodalization8ive throttle ty&es

Green 6one Blue 6one "

Red 6one 7

Blac, 6one ;

Li#ht )lue 6one 5

Considering

-5 Boxes

7- Radial

sector 5 Rin#s

@ax &o*er channel

"0

euivalent

channels


17/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $*

G r u p p o R


P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

$P Nodalization

8our layers+ 8irst hori6ontal &art connected to the coolant channel outlets ()lue+

"+ 8irst vertical &art u& to the !L axis (oran#e+

7+ econd hori6ontal &art alon# the !L (#reen+

;+ econd vertical &art to account %or the nearly se$is&herical

sha&e (yello*+


18/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $%

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

$P Nodalization

4he three di%%erent layers$odelled )y several )ranches

E'#'1 the %irst layer – hori6ontal

"5 9)ranches: connected to the

"0 euivalent core channel

(red circles+


19/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% $+

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

RPV Nodalization

Not !$$ h!""#$%(#)(#%#"t#*&


20/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &'

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

#OOP Nodalization !includin%

S"9tandard: nodali6ation techniueGeneral rules %ollo*ed .unction only connected to a &i&e Ratio len#th o% t*o consecutive nodes

stays *ithin 0'5 – "'0 unction at inlet and outlet o% nodes only

G $odeled till the isolation valves

3u$& ho$olo#ous curves ta,en %ro$ FA/A nodali6ation

2 $oo)% +o*#$#*1 $oo) (#)(#%#"t#*


21/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &$

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

'oderator syste

$oo)% +o*#$#* - 1 $oo) (#)(#%#"t#*

'#!t #.h!"/#(%P(i+!( %i*# o

+o*#(!to( oo$#(

S!#t i"#tio"

Mo*#(!to(

)u+)

Mo*#(!to(*o3"o+#(

S!#t i"#tio" )o(t

Pump homologous curves given by NA-SA


22/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &&

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Neutron (Sec #i)raries odel * eneration

ENDF/B-! N"#$N"#$%ulti& 'Sec

()* &roups+

,E!#S,E!#S

v. .0v. .0

'Secs ibraries'Secs ibraries

(1 &roups+(1 &roups+

1D 2ransport

Calculations


23/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &3

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Neutron (Sec #i)raries Code Adanced lattice &h(sics code HEL'/HEL'/ used to calculate the cross

section sets

HEL'/HEL'/ is a neutron and 'amma trans&ort code or lattice !urnu&5 in'eneral t.odimensional 'eometr(

#eelo&ed !( /./4, /./4,

;;

/candpo


24/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &(

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Neutron (Sec #i)raries odel Channel!(channel !urnu& distri!ution su&&lied !( $ASA


25/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &5

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Neutron (Sec #i)raries odel *or e&ery composition a cross section set is generated

Each "ross /ection set contains tables 8or>

Fast and Thermal #iMusion CoeGcients

Fast and Thermal Ca&ture Cross Sections

Fast and Thermal Fission Cross Sections

Fast and Thermal $uFission Cross Sections

Remoal Cross Sections ,/rou& ; 2-

Inerse $eutron @elocities

Assem!l( #iscontinuit( Factors ,A#Fs-

Photoneutron eMect ,su&&lied !( $ASA- to !e taen into account

directl( in $ESTLE in&ut

N (S #i) i d l


26/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &)

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Neutron (Sec #i)raries odel Seeral HEL'/HEL'/ in&ut decs deelo&ed?

Fuel Channel ,hea'onal lattice- Fuel Channel N :oderator

CR a!sor!ers ,!lac B 're( CR5 u&&er B lo.er &art-

ReKector? Radial5 6ottom5 and To&

8uel Channel 8uel Channel Re%lector 8uel Channel CR

N (S #i) i d l


27/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &*

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Neutron (Sec #i)raries odel

Inter&olation in Fie#imensional Ta!lesInter&olation in Fie#imensional Ta!les

For C$AII core model FieFie Inde&endent Parameters .ill !e

used?

;- Fuel Tem&erature ,#o&&ler Feed!ac-

2- Coolant #ensit( ,@oid EMect-

"- Coolant Tem&erature


28/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &%

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Cross Section 'odellin%

A42C!ACRO'exe

(8OR4RAF ?0 &ro#ra$+

3e4erence

Cross Section

alues

C3#SS

SEC2!#N

!B3A3!ES(nemtab5 nemtabr65

nemtabr615 nemtabr675

nemtabr6)+

Cross-Section

ariation

Coe44icients

5D LINEAR

INTERPOLATION ROUTINE

(LINT5D)

LEAST SQUARE

METHOD(MC)

?ref

Coolant ρ ∂

Σ∂

Moderator B∂

Σ∂

Fuel T ∂

Σ∂

Moderator T ∂

Σ∂

Coolant T ∂

Σ∂

C S i ' d lli


29/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% &+

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

Final @ersion o theAT1CHACROSS &ro'ram

5 lines Fortran&ro'ram

Automaticall( &erorm

adhoc inter&olations5

or seeral ones o thereactor core

@ariation coeGcientcalculation

$ESTLE in&ut .ritin'

Cross Section 'odellin%

?ref

Coolant ρ ∂

Σ∂

Moderator B∂

Σ∂

Fuel T ∂

Σ∂

Moderator T ∂

Σ∂

Coolant T ∂Σ∂

CR in%or$ation

(4y&e1 an#les1 nu$)er+

FE4LE IF324

+D N, .H l d d l


30/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3'

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o a

G r a d o

G r a d o

+D N, - .H cou/led odel "# $% nodes o!tainin' ).ei'hted+ eed!ac rom TH model

$ESTLE sendin' !ac &o.er distri!ution to FA heat structures

Po.er

%E/LE%E/LE

Fuel Channel

TH model

:oderator

TH model

Coolant#ensit(

Coolant Tem&erature

:oderator Tem&eratur

e

6oronConcentrati

on

Fuel Tem&eratur

e

RELAP5-3RELAP5-3

+D N t ,i ti d l


31/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3$

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

+D Neutron ,inetic odel $ESTLE "# $% model characteristics?

Hea'onal lattice "'"; c$ &itch

;0 aial la(ers or actie core? 7"03 cm

; la(er or the 6ottom ReKector?


32/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3&

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

CR odelin% ;8 Control Rods

inserted dia'onall(,;327-

6lac CR Haniuma!sor!er

/re( CR Steela!sor!er

Each CR has upper and lo


33/49


G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

88 )) /9 8

)):

)70

/*9

/:

:0

:9

CR odellin% Four Cross Sections Li!raries calculated or CR modellin'

CR DSec corrections due to the "# 'eometr( eMects introduced usin' "#:C$P7 :onte Carlo Simulations

88 )) /9 8

)):

)70

/*9

/:

:0

:9

CR and Fuel Channels Section NESTLE modelling

+D N, .H l d d l F l Ch l


34/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3(

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

+D N, - .H cou/led odel - Fuel Channels

Atucha II $PP 280 channel280 channel RELAP7"# TH model used

o TH channels modeled B cou&led accordin' to?

H(draulic characteristics ,throttled t(&e4unthrottled-

Rom!oidal su!&lena !elon'in'

Po.er distri!ution

Transient t(&e

Code resources0 0" 07 0; 05 0- 0 0 0? 0 " 7 ; 5 - ? "0 " "" "7 "; "5 "- " " "? 70 7 7" 77 7; 75 7- 7 7 7? ;0 ; ;" ;7 ;; ;5

BGB8

BE

BD

BC

BB

BA

BL

AH

A!

AG

A8

AE

AD

AC

AB

AA

AL

LH

L!

LG

L8

LE

LD

LC

LB

LA

" "

"

"

" "

"" "

7 - "

" "

" " 7-" " "

" " 7 7 " "7 7 7 7

"

" " " 7

7 7 " "7 7 7 7

" " 7 7 7 7

- " " "; 7 7 7; ; ; ;- 7 7 7 " "

7 " " ; ; 7 7; ; ; ;

" " 7 7 7 ; ;

7 7 7 "; ; ; ;; ; ; ;

7 -

" " 7 7 7 ;

; ; ; 7; ; ; ;; ;

" - 7 7 ;

; 7 7 "5 ; ; ;; ; 5 5

"

" " 7 7 ; ;

7 7 7 "5 ; ; ;; 5 5 5

"

" " 7 7 7 ; ;

; 7 7 "5 5 ; ;; 5 5 5

" "

" " 7 7 ; ;

; 7 7 75 5 ; ;; ; 5 5

"

" " 7 7 7 ;

; 7 7 "5 ; ; ;; ; 5 57 7 ; ; "

- " ; ; 7 7; ; ; ;; ; ; ; - 7 7

7 " " ; ; 7 7; ; ; ;7 ; ; ; " 7 7

" " 7 7 7 7; ; ; ;

" " 7 7 7 7 ; ;

- " " ; 7 7 7; ; ; ;- 7 7 7 " " "

" 7 7 7 "7 7 7 7

" " " 7 7 7

" " "

" " " " 7 7 7

" " " " - 7 7

" " "

" " " " " "

"

" " " "

"

-

7 7 7 7

"

"

" "


35/49


G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

+D N, - .H cou/led odel - Fuel Channels

280 RELAP7 Fuel Channels cou&led .ith


36/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3)

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

+D N, - .H cou/led odel - +D 'oderator tan0

:oderator :odel usin' RELAP7"# "# com&onents

&ossi!ilit( to simulate .ith hi'h de'ree o realism the !oron clouds calculated !(

CF# simulation o as(mmetric transients

@er( so&histicated ma&&in' scheme resulted rom the use o C(lindrical "# THCom&onents cou&led .ith Hea'onal $% cells

Q radial sectors radial sectors

Q 0B 0 B 0 C 02 aDial layers 8or0B 0 B 0 C 02 aDial layers 8or

ottom Reector$ "ore Acti&e )one$ottom Reector$ "ore Acti&e )one$

op reectorop reector

Q 0 a)imuthal sectors0 a)imuthal sectors3 (oderator ank F%E/LE mesh o&erlay

'odellin% the )oron eer%ency in1ection


37/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3*

G r u p p o R


a r e S .

P i e r o a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

'odellin% the )oron eer%ency in1ection

syste 6oron Inection Clouds calculated !( a &reious CF#

CFD T:

code calculation

reconstructed !( adhoc T:#P1$ com&onents in the "# :oderator Tan

Inection onesInection ones

Com&arison CF# * RELAP7"#Com&arison CF# * RELAP7"#

inected mass o !oroninected mass o !oron

RELAP7"# :ass o !oronRELAP7"# :ass o !oron

distri!ution in diMerent la(ersdistri!ution in diMerent la(ers

2345 Channels6 Nodalization Resources


38/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3%

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

345 Channels Nodalization Resources

$um!er o H(draulic $odes? 753


39/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% 3+

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

+D N, Cou/led .H SS Results

Core SS conditions?

Hot Full Po.er? 2;0 /W

$ominal alues or Fuel5 Coolant and :oderator Tem&eratures distri!ution

CR in ,$ASA con='uration-

G0 ?; in

G"0 - in

G70";'5 in

0 ;'"? in

hut/O%% ("0 70+ All Rods Out

6oron Concentration? 007 &&m

SS Radial Po7er


40/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% ('

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

SS - Radial Po7er %eM 099770

F( ;"8

:aimum:aimum

:in ;0; :W:in ;0; :W

:a 7 :W:a 7 :W

:inimum

SS Radial Po7er


41/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% ($

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

SS - Radial Po7er

Radial Po.er ? S&atial Form Function

SS Noralized Reactor A8ial Po7er


42/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% (&

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

SS Noralized Reactor A8ial Po7er

ADial Po


43/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% (3

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

Fuel Channels 'ass Flo7:ass Flo. &er Assem!l( %'4sU

SS Cou/led Codes .H


44/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% ((

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

SS Cou/led Codes .H

ParaetersAll the main TH &arameters coner'ed to SSreerence aluesE'5 moderator Tan tem&erature distri!ution

Botto$ 4o& Re%lector

Active Core

#9#OCA 5 ;A in C#3 Sa/le Results


45/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% (5

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

L6LOCA 0; A in CL2 ,reerence #6A or Atucha2-

Actuation oScram !( all CRs ? N003 s

Emer'enc( 6oron Inection S(stem ? N 0" s

:CP; B 2 rundo.n ? N003 s

CR com&letel( inserted ? N"< s

End o 6oron Inection in moderator tan ? N"9; s

%o /a8ety threshold eDceeded

#9#OCA 5:;A in C#3 - Sa/le Results

#9#OCA 5 ;A in C#3 Sa/le Results


46/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% ()

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

#9#OCA 5:;A in C#3 - Sa/le Results

Reactor Po.erReactor Po.er Pressure Trends in 1P andPressure Trends in 1P and

PRPR

Fuel Clad Tem& in Central and Hot ChannelFuel Clad Tem& in Central and Hot Channel@oid Fraction in Central and Hot@oid Fraction in Central and Hot

ChannelChannel

'CP Shaft seizure Sa/le Results


47/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% (*

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

'CP Shaft seizure - Sa/le Results

:CP2 Shat seiure in ; s

:CP; continues o&eration

CRs scram? N0; s

CRs com&letel( inserted? N"3" s

%o /a8ety threshold eDceeded Reactor Po.erReactor Po.er

@oid Fraction in Central B Hot@oid Fraction in Central B Hot

ChannelChannel

: /.: 1.: 7.: ).: ;.: 8.: *.: 9.: 0.: /:.:

2ime (s+

-./:

:

./:

.1:

.7:

.):

.;:

.8:

o

i d

F r a c t i o n

JinGra% ;' / 0"/"-/"00A

KKK @C3Lha%tLei6ure void#"500;0000

K K K K K K K K K K K K K K K K K

MM M @C3Lha%tLei6ure void#"500A0000

M M M M M M M M M M M M M M M M M

NNN @C3Lha%tLei6ure void#"50"0000

N

N

N

N

N

N

N

N N

N

N

N

N

N

N

N

OO O @C3Lha%tLei6ure void#""0;0000

O O O O O O O O O O O O O O O O

EEE @C3Lha%tLei6ure void#""0A0000

E E E E E E E E E E E E E E E

!!! @C3Lha%tLei6ure void#"""0000

!

!

!

!

!

!

!!

!

!

!

!

!

!

!

Fuel Clad Tem& in Central and Hot ChanneFuel Clad Tem& in Central and Hot Channe

FC 9loc0a%e !9D9A" Sa/le Results


48/49

RELAP5-3D User Seminar – Idaho University Campus, Idaho a!!s, USA – "ovem#er $%-&', &''% (%

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

FC 9loc0a%e !9D9A" - Sa/le Results

Hot channel ," :W- total !loca'e in 02 s

$o scram si'nal actuated

/e&ere *uel Assembly damage

: .1; .;: .*; .:: .1; .;: .*; 1.:: 1.1; 1.;:

2ime (s+

-;.:

:

;.:

:.:

;.:

1:.:

1;.:

7:.:

7;.:

% a s s F l o < 3

a t e ( = g / s +

JinGra% ;' / 0/"/"00A

KKK CFA"8CBLOCHAGE $%lo*.""00000

K K K K K K K K K K K K K K K K K K K K

Fuel Clad Tem& in 6loced ChannelFuel Clad Tem& in 6loced Channel

6loced Channel Po.er6loced Channel Po.er

6loced Channel :ass Flo.6loced Channel :ass Flo.

Conclusions


49/49

G r u p p o R


a r e S .

P i e r o

a

G r u p p o R


a r e S .

P i e r o

a

G r a d o

G r a d o

Conclusions /R$SP/41$IPI deelo&ed or Ar'entinean electric utilit( $ASA so&histicated

RELAP7"# models or Atucha II $PP

"# $% TH )280 channel nodaliation+ .as &resented

"# $% TH model setu& re>uired stron' interactions .ith other technolo'(=elds ,e'5 CF#5 neutron DSecs 'eneration-

RELAP7"# models calculations .ill constitute the Cha&ter ;7 o the FSAR orthe Atucha II licensin'

RELAP7"# demonstrated to !e a er( so&histicated tool5 allo.in' a detailed

modellin' o all releant &henomena B &eculiarities o the Atucha II desi'n %e( &oints or the code im&roement .ere identi=ed and su''ested to I$L

E'?

Increase o the allo.a!le Tri& cards

Increase the num!er o "# @olumes &er :ulti# com&onent

Online Cross Section li!raries inter&olation

Automatic Calculation o Reactiit( com&onents ,e'5 #o&&ler reactiit(5 coolanttem& reactiit(5-

Further .ors are on'oin' at /R$SP/41$IPI in order to?

Com&lete models >uali=cation

Etend the model to a ull RP@ "# TH re&resentation5 includin' the simulation o all

Documents

Atucha-2 PHWR Three Dimensional Neutron Kinetics Coupled Thermal-hydraulics Modelling and Analyses