TRACTEBEL ACTIVITIES WITH FRAPCON & FRAPTRAN: … Meetings/Manchester 2012/TE FR… · TRACTEBEL...

TRACTEBEL ACTIVITIES WITH FRAPCON &

FRAPTRAN: OUTCOMES & EXPECTATIONS

CHOOSE EXPERTS, FIND PARTNERSCHOOSE EXPERTS, FIND PARTNERSCHOOSE EXPERTS, FIND PARTNERSCHOOSE EXPERTS, FIND PARTNERS

FRAPTRAN: OUTCOMES & EXPECTATIONS

2012 FRAPCON/FRAPTRAN User Group Meeting,

Manchester, UK, 7 September 2012

Z. Umidova, J. Zhang (GDF-SUEZ)

OUTLINE

• Introduction

• IAEA FUMEX III

• OECD RIA Benchmark

• HALDEN LOCA Benchmark

7/9/2012 2FRAPCON/FRAPTRAN User Group Meeting, Manchester, UK

• HALDEN LOCA Benchmark

• OECD UAM II-1 Fuel-physics PWR cases


INTRODUCTION

• Objectives: Assessment of FRAPCON/FRAPTRAN for applications to- R&D and knowledge transfer

• Better understanding of fuel behaviour in normal and transient conditions

• Pre- and post-test calculations to support test design and results interpretation

- Operational support- Operational support

• Independent verification of the fuel vendor’s fuel rod design and modifications

- Licensing support

• Independent verification of fuel vendors’ LOCA/RIA safety analysis and reloads fuel safety evaluation

• Feasibility study for burnup extension

- Generation of fuel rod input data for neutronics codes

• Realistically simulation of fuel behaviour for core physics calculation


INTRODUCTION

• Key fuel rod behaviour issues- Fission gas release (FGR) at high duty/burnup

- Rod internal pressure (no cladding lift-off) at high duty/burnup

- Cladding corrosion and hydring at high duty/burnup

- Pellet-Cladding Mechanical Interaction (PCMI or PCI) during Condition II - Pellet-Cladding Mechanical Interaction (PCMI or PCI) during Condition II transients

- Evolutions of LOCA/RIA safety criteria (burnup or corrosion performance based criteria)


IAEA FUMEX-III

• Priority cases: Co-operation between PNNL, GDF-SUEZ and NRI

PCMI PCI LOCA RIALoad follow transients Transients Gad/Nb

Normal operation FGRPlant type MOX

Mechanical interaction Severe transients FGR; Temperature etc

PCMI PCI LOCA RIA transients Transients Gad/Nb operation FGR

IFA 629.1 (PNNL)

Riso3 GE7 (PNNL);

IFA535 5 rod 9 (PNNL)

Riso 3 rod II5 52G (PNNL)

PRIMO rod (BD8) (PNNL)

OSIRIS - 2 rod HO9 (PNNL)

GAIN Gd 701 and 301 (PNNL)

WWER MIR Ramp rods 41 48 50 51 (NRI)

LWR SUPERRAMP PK6 and PW3 (GDF-SUEZ); INTERRAMP 10G 20G (PNNL)

IFA 650.2 (PNNL+NRI); Suggest for adding more cases IFA650.3-7

FK1 and FK2 (GDF-SUEZ+NRI); Suggest for adding recent NSSR and CABRI test (e.g., OECD RIA benchmark cases)

IFA 519.8/9 Rods DC and DK (PNNL)

US 16x16 PWR TSQ002 TSQ022 (PNNL); AREVA idealised case (GDF-SUEZ)

Plant type MOX


IAEA FUMEX-III

• Studsvik PWR Super-ramp Tests

- Power history and axial power profile impact significantly the final results

- New fission gas release model (FRAPFGR) underpredicts the FGR for PK rods (except PK6 high burnup test) PK6 high burnup test)

- Mechanical calculations:

- Can not be compared due to insufficient information about measurements (time, position,…)

- No rod failure threshold criterion determined from the calculations: strain (PCMI) or stress (PCI/SCC) dominated failure?


IAEA FUMEX-III

• AREVA Idealised case

- Rod average burnup and cladding oxided thickness are well predicted with the defined power history and default models 8

9

10

11

12

13

Ave

rage

Fis

sion

Gas

Rel

ease

(%)

MASSIH

FRAFGR

FRAPFGR biased

3 cyclesdefault models

- Default Massih model underpredicts the fission gas release at high burnup

- New fission gas release model (FRAPFGR) overpredicts the fission gas release at high burnup and underpredicts at moderate burnup (~35 MWd/kg)

- Mechanical model: was not analysed for this case

0

1

2

3

4

5

6

7

8

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85

Ave

rage

Fis

sion

Gas

Rel

ease

(%)

Burnup (MWd/kg)

4 cycles

7 cycles


IAEA FUMEX-III

5

5.5

6

Default model

• NSSR BWR RIA Tests

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

0 5 10 15 20 25 30 35 40 45 50

Fis

sio

n g

as re

leas

e (%

)

Rod average burnup (MWd/kg)

Default model

FRAPFGR no biased model

FRAPFGR biased (-0.75) model

Measure


IAEA FUMEX-III


1.6

1.8

2

Measured

default model

FEA model with 0.07 friction coefficient

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 1 2 3 4 5 6 7 8 9 10

Cla

dd

ing

axi

al e

lon

gat

ion

(mm

)

Time (s)





IAEA FUMEX-III


- Rod average burnup, rod average ethalpy, cladding oxided thickness, rod internal pressure during base irradiation are well predicted with the defined power history and default models

- New fission gas release model (FRAPFGR) allows predicition of fission gas release during RIA transient but overpredicts base irradiation fission gas release � possible

to use the default model for base irradiation (FRAPCON) and FRAPFGR for transient (FRAPTRAN) calculations?

- Mechanical model: diamteral changes, elongations, stress, strain, failure

- defaut model predicts reasonably the mechanical properties but the behaviour is atypical,

- FEA model has a better behaviour but depends strongly on the friction coefficient assumption (code failure occurs with a default plenum volume as defined in report)

=> this model is not recommended to be used by PNNL


OECD RIA BENCHMARK

• NSSR BWR RIA Capsule Tests

- The models with default values for two boundary condition models predict very high cladding temperatures

- The sensitivity cases with higher HTC conduct to the lower cladding surface - The sensitivity cases with higher HTC conduct to the lower cladding surface temperature

0

50

100

150

200

250

300

0 1 2 3 4

En

erg

y d

ep

osi

ted

in

th

e w

ho

le r

od

let

(ca

l/g

)

Time (s)

heat model

coolant model

0

500

1000

1500

2000

2500

3000

3500

0 0.5 1 1.5 2 2.5 3 3.5Cla

dd

ing

su

rfa

ce t

em

pe

ratu

re (

°C)

Time (s)

VA-1

heat model

coolant model


OECD RIA BENCHMARK

• CABRI RIA Tests

- The ‘coolant’ model predicts very low cladding temperature

=> Impact on mechanical behaviour

0

100

200

300

400

500

600

700

800

900

1000

0 5 10 15 20

Cla

dd

ing

ou

tsid

e t

em

pe

ratu

re (

°C)

Time (s)

case 4

case 3

0

1

2

3

4

5

6

0 5 10 15 20

Cla

dd

ing

elo

ng

ati

on

(m

m)

Time (s)

case 4

case 3


HALDEN LOCA TESTS SIMULATION

• Modelling of IFA-650.3-5

- Use of ‘coolant’ option is difficult

=> only use of ‘heat’ model is possible

- Plenum gas temperature model lead to very high pressure- Plenum gas temperature model lead to very high pressure

=> use of new release of FRAPTRAN 1.5 with imposed plenum temperature



• Overprediction of rod internal pressure

- Underprediction of burst time



• Overprediction of rod internal pressure

=> Little impact on clad elongation and strain



• FRAPCON and FRAPTRAN codes are demonstrated capable of simulating fuel behaviours (ballooning and burst) during LOCA for a single rod with high burnup (> 80 MWd/kgU)

• FRAPTRAN code tends to overestimate internal rod pressure • FRAPTRAN code tends to overestimate internal rod pressure leading to conservative predictions of time of burst and ballooning

- The overestimation of internal gas pressure should be improved together with model modification of plenum gas temperature model

• Thermal hydraulic boundary condition model should be improved in order to predict the cladding temperature


OECD UAM II-1 FUEL-PHYSICS PWR CASES

• Objective: evaluation of uncertainties associated with modelling of the fuel temperatures with stand-alone fuel rod codes

- Case 2a (steady-state) and case 2b (transient) PWR numerical tests

• Based on experiments but with modified dimensions and other parameters in order to present the reactor of interestthe reactor of interest

- Case 5a (steady-state) PWR experimental test

• Based on Halden IFA-429 experiment

• High burnup (65 MWd/kg)

• Transient specification not available at moment of calculations (to be provided)

• Main parameters of interest at different time steps are:

- Centreline fuel temperature

- Pellet outside fuel temperature

- Axial fuel temperature profile

Doppler Temperature



• The specified input uncertainties are implemented

- Manufacturing uncertainties

• Case dependent: specific to each experiment• Case dependent: specific to each experiment

- Uncertainties in the boundary conditions

• The same for all cases

• Modelling is dependent on steady-state or transient simulation

- Uncertainties in the parameters in the code models

• Code dependent



• Code uncertainties: specified variations and assumed normal distribution

Parameter Variations DistributionParameter Variations Distribution

Fuel Thermal Conductivity ±0.5 W/m-K NormalFuel Thermal Expansion ±15% NormalCladding Thermal Conductivity ±5 W/m-K NormalCladding Thermal Expansion ±30% NormalGas Conductivity ±0.02 W/m-K NormalHeat Transfer Coefficient ±5.0% Normal



• Boundary conditions: specified variations and assumed normal distribution

- 2b (transient) Parameter Variations Distribution

Coolant Flow Rate ±2.0% NormalCore inlet coolant enthalpy ±5700 K NormalCore Pressure ±3.0% NormalPeak power pulse ±5.0% Normal



• FRAPCON steady-state and/or FRAPTRAN transient input models

- Specified manufacturing parameters

- Specified boundary conditions

- Default FRAPCON and FRAPTRAN models and options

- Initialization of restart file option between FRAPCON and FRAPTRAN codes necessary for uncertainty propagation



• Initial state : end of case 2a (40 MWd/kg)

• Power pulse: modelled as specified

2.5

3

x 104 TMI-1 Transient Pulse

specified

• Axial power distribution: same as for steady-state case

• Analyses of results at 7 different time steps: t= 0.065s, 0.082s, 0.084s, 0.1s, 0.15s, 0.37s, 1s

0.05 0.06 0.07 0.08 0.09 0.1 0.11 0.120

0.5

1

1.5

2

Time (s)

Pow

er (

kW/m

)



• Nominal fuel centreline temperature with lower and upper bounds

• standard deviation dependent 1 600

1 800

2 000

• standard deviation dependent

on time

0.5 °C -> 23 °C

0.00

5.00

10.00

15.00

20.00

25.00

0 0.2 0.4 0.6 0.8 1 1.2

Centreline tempera

ture

Std-D

ev. [K

]

Time [s]

0

200

400

600

800

1 000

1 200

1 400

1 600

0.0 0.2 0.4 0.6 0.8 1.0 1.2

Fu

el

cen

tre

lin

e t

em

pe

ratu

re (

K)

Time (s)

Nominal

Upper bound

Lower bound



• Nominal pellet outside temperature with lower and upper bounds

2 000

2 500

40.00

50.00

tempera

ture

0

500

1 000

1 500

2 000

0.0 0.2 0.4 0.6 0.8 1.0 1.2

Pe

llet

ou

tsid

e t

em

pe

ratu

re (K

)

Time (s)

Nom

Upper bound

Lower bound

• Standard deviation is dependent

on time: 0°C -> 45 °C (higher

than for Fuel Centreline

temperature)

0.00

10.00

20.00

30.00

40.00

0 0.2 0.4 0.6 0.8 1 1.2

Centrelinete

mpera

ture

Std

-Dev. [K

]

Time [s]


• Nominal Doppler temperature with lower and upper bounds

-bigger deviation than for fuel centreline and pellet outside 1 600

1 800

2 000


centreline and pellet outside temperatures

-Large scatter of maximum axial Doppler temperature

1680

1700

1720

1740

1760

1780

1800

1820

1840

1860

0 10 20 30 40 50 60 70 80 90 100

Sca

tte

r o

f D

op

ple

r te

mp

ratu

re a

t p

eak

po

we

r p

uls

e[K

]

Number of samples

0

200

400

600

800

1 000

1 200

1 400

1 600

0.0 0.2 0.4 0.6 0.8 1.0 1.2

Do

pp

ler

tem

pe

ratu

re (

K)

Time (s)

Nom

Upper bound

Lower bound


• Participation in the IAEA fuel work FUMAC

• Development of LOCA/RIA fuel safety assessment

FUTURE WORK

TRACTEBEL ACTIVITIES WITH FRAPCON & FRAPTRAN: … Meetings/Manchester 2012/TE FR… · TRACTEBEL...

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Transcript of TRACTEBEL ACTIVITIES WITH FRAPCON & FRAPTRAN: … Meetings/Manchester 2012/TE FR… · TRACTEBEL...