Pre-irradiation Characterization of Beryllium for High ...Boudewijn Pijlgroms a NRG Petten, the Netherlands Ceramic Breeder Blanket Interactions CBBI-13, 1 December. Outline Objectives

Status of the high Status of the high fluencefluence irradiation of irradiation of ceramic pebbles in the HICU projectceramic pebbles in the HICU project

Hans Hegeman, Jaap van der Laan , Kees Beemsterboer, Sander Kamer and

Boudewijn Pijlgroms

a NRG Petten, the Netherlands

Ceramic Breeder Blanket Interactions CBBI-13, 1 December

OutlineOutline

Objectives of the high fluence irradiation Nuclear characteristicsTest matrix and designThermal design of the irradiation devicePre-irradiation characterisationOutlook

ObjectivesObjectives

“Investigation of a) the impact of neutron spectrum and b) the influence of constraint conditions

on the thermo-mechanical behavior of breeder pebble-beds in a high fluence irradiation”

HICU Fluence (E>0.1 MeV 1026 n/m2) 1.5

Fluence (E>1 MeV 1026 n/m2) 0.7 6Li enrichments Li4SiO4 (%) 0.06, 7.5, 20 6Li enrichments Li2TiO3 (%) 0.06, 11, 30 6Li Burnup (%) 0.74 - 13

Neutron damage (dpa) 20-25

Temperatures (°C) 600-650 750-800

Irradiation characteristicsIrradiation characteristics

0 2 4 6 8 10 120

10

20

30

40

50

0.06% unshielded

7.5% unshielded7.5% shielded

20% shielded

EXOTIC 7, 8

DEMO blanket 1 FPY

Dis

plac

emen

t dam

age

in O

Si (d

pa)

Total Lithium burnup in OSi (%)

Near first wall

Near back plate

DEMO blanket 20.000 hrs

Spectrum effect in Spectrum effect in OrthosilicateOrthosilicateEffect is calculated for the actual vertical location of the specimen

Specimen 7.1 with Othosilicate 7.5% 6LiSpecimen 8.1 with Othosilicate 20% 6Li enriched

10-3 10-2 10-1 100 101 102 103 104 105 106 107

1012

1013

1014

Neu

tron

Flux

energy (eV)

OSi 7.5% shielded OSi 20% shielded OSi 7.5% OSi 20%

Spectrum effect in Spectrum effect in MetatitanateMetatitanateEffect is calculated for the actual vertical location of the specimen

Specimen 5.1 with Metatitanate 7.5% 6LiSpecimen 4.1 with Metatitanate 30% 6Li enriched

10-3 10-2 10-1 100 101 102 103 104 105 106 1071011

1012

1013

1014

Neu

tron

Flux

energy (eV)

MTi 7.5% shielded MTi 30% shielded MTi 7.5% MTi 30%

Test MatrixTest Matrix

NRG-ID. Suppl. % enrichment High Constraint High T

High Constraint Low T

Low ConstraintHigh T

Low ConstraintLow T

Total

NRG-126 FzK OSi 20 2 1 1 4 NRG-125 FzK OSi 7.5 2 1 1 1 5 NRG-129 FzK OSi 7.5 1 1 NRG-124 FzK OSi 0.06 1 1 2 5 1 3 3 12 NRG-120 CEA MTi 30 2 1 1 4 NRG-119 CEA MTi 11 2 1 1 1 5 NRG-118 CEA MTi 0.06 1 1 2 NRG-121 CEA MTi 7.5 1 1 2 NRG-122 CEA MTi 7.5 1 1 2 NRG-123 CEA MTi 7.5 1 1 2 NRG-130 CEA MTi 7.5 1 1 2 NRG-131 CEA MTi 30 1 1 2

6 2 7 6 21 NRG-115 JAERI MTi 31 1 1 1 3 NRG-116 JAERI MTi-5% 31 1 1 1 1 4 NRG-117 JAERI MTi-10% 31 1 1 1 3 NRG-127 JAERI MTi 7.5 1 1

3 1 4 3 11 Total Total 14 4 14 12 44 HiCon 18 LoCon 26

Capsule designCapsule design

8 drums loaded with pebble stacksEach drum is separated by heat barriers/radiation shieldsCentral discs for determination of nuclear heating (gamma)On-line tritium monitoring (entire capsule) including moisture

First containmentSecond containment

(9x4

7+7x

10+1

5)50

8

Drum 8: 650-850°C

Drum 7: 850°C+ dosimeterset

Drum 6: 850°C


Drum 4: 850°C

Drum 2: 650°C


5981

5

300

CL-core

233

10(7

x)47

(9x)

3

Design of the irradiation capsuleDesign of the irradiation capsule

Stainless steel, 0,9mm tube

1,9mm Cadmium/Hafnium

Stainless steel, 0,2mm tube

QUATTRO, ID Ø29 mm

(Ø28,8) Stepped OD containment)

Ø22,8H7 (ID containment)

Eurofer cladding, Ø4xØ5 mm. 51°

(0,55)

7

stc15,2

Vanadium alloy 'drum':

Eurofer cladding, Ø9 x ±Ø11 mm.

Tc holes: Ø1,1 mm

28°

R0,2

stc9,5

22°

4,92

R large spec

R small spec 3

R small spec 2

R small spec 1

Ø11,1H7

R6,1

51°

Ø6,1H7(3x)

Ø22

,8g6

(OD

dru

m)

Gas tube 2,5x1,7mm

Thermocouples

123

4

Location of the ceramic pebble stacksLocation of the ceramic pebble stacks

Tccenter

Tccladdin

g spec.materialT

(central)P (n,a)(W/cc)

1 1.2 mti-31-10% NRG-117 JAERI 650 12.6DRUM 2.2 osi-7.5 NRG-125 EU-FZK 650 4.4

1 1 1.3 mti-31 NRG-115 JAERI 650 12.31.4 mti-31-5% NRG-116 JAERI 650 11.81.5 mti-31-10% NRG-117 JAERI 650 10.8

1 2.1 mti-11 NRG-119 EU-CEA 650 6.7DRUM 1.1 mti-ref+++ NRG-130 EU-CEA 650 5.9

2 1 9.3 mti-ref NRG-121 EU-CEA 650 4.72.4 mti-11 NRG-119 EU-CEA 650 7.42.5 mti-0.06 NRG-118 EU-CEA 650 0.5

1 1 4.1 mti-30 NRG-120 EU-CEA 800-850 18.6DRUM 4.2 mti-30 NRG-120 EU-CEA 800-850 20.9

3 1 3.3 mti-31 NRG-115 JAERI 800-850 22.93.4 mti-31-5% NRG-116 JAERI 800-850 21.53.5 mti-31-10% NRG-117 JAERI 800-850 20.5

9.1 mti-31-10% NRG-117 JAERI 800-850 21.7DRUM 1 9.2 mti-ref+ NRG-122 EU-CEA 800-850 6.4

4 5.5 mti-ref++ NRG-123 EU-CEA 800-850 7.01 6.4 osi-7.5 NRG-125 EU-FZK 800-850 12.2

4.5 mti-ref+ NRG-122 EU-CEA 800-850 8.7

Location of the ceramic pebble stacksLocation of the ceramic pebble stacks2

5.1 mti-ref+++ NRG-130 EU-CEA 800-850 9.4DRUM 1 5.2 osi-7.5+ NRG-129 EU-FZK 800-850 12.3

5 1 5.3 osi-20 NRG-126 EU-FZK 800-850 24.95.4 mti-30 NRG-120 EU-CEA 800-850 28.34.3 mti-30 NRG-120 EU-CEA 800-850 34.7

1 1 6.1 osi-7.5 NRG-125 EU-FZK 800-850 13.0DRUM 6.2 osi-7.5 NRG-125 EU-FZK 800-850 13.0

6 1 6.3 be-peb 0 EU-Be 800-850 0.04.4 mti-0.06 NRG-118 EU-CEA 800-850 1.46.5 osi-0.06 NRG-124 EU-FZK 800-850 3.7

1 1 7.1 mti-11 NRG-119 EU-CEA 800-850 12.8DRUM 7.2 mti-11 NRG-119 EU-CEA 800-850 12.2

7 1 7.3 mti-ref NRG-121 EU-CEA 800-850 9.87.4 mti-11 NRG-119 EU-CEA 800-850 13.07.5 mti-7.5 NRG-127 JAERI 800-850 8.8

1 1 8.1 osi-20 NRG-126 EU-FZK 800-850 20.6DRUM 8.2 osi-20 NRG-126 EU-FZK 800-850 19.4

8 1 9.4 mti-ref++ NRG-123 EU-CEA 650 6.88.4 osi-7.5 NRG-125 EU-FZK 650 11.78.5 osi-0.06 NRG-124 EU-FZK 650 3.2

1 3.2 mti-31-5% NRG-116 JAERI 800-850 24.7DRUM 3.1 mti-31 NRG-115 JAERI 800-850 19.6

9 1 8.3 mti-ref++++ NRG-131 EU-CEA 650 27.39.5 osi-20 NRG-126 EU-FZK 650 22.52.3 mti-30 NRG-120 EU-CEA 650 21.9

4 20

Capsule designCapsule design

Thermocouple locations Vanadium drum

Cadmium shield manufacturingCadmium shield manufacturing

Fabrication route selected: uniaxial compression of cadmium/hafnium ring inside two concentric tubesThin cladding on the inside, containment tube on the outside

Gas gaps

ThermalThermal Design of HICUDesign of HICU

2D and 3D analysesTemperature limits for Cadmium (nor melting allowed)Thermocouples included

Thermal Design of HICU (2)Thermal Design of HICU (2)

Results for central drum with all specimens at 850°CResults for lowest drum 9, with large pebble stack at 850°C and small stacks at 650°C


3D models required due to asymmetry and stress analysis


High thermal gradients within the pebble stacks due to the low thermal conductivity of the ceramic breeder

Central drum Bottom drum

Cross section temperaturesCross section temperatures

Cross section temperatures (2)Cross section temperatures (2)

Ther

moc

oupl

e di

strib

utio

nTh

erm

ocou

ple

dist

ribut

ion

PrePre--stressing pebble stacksstressing pebble stacks

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0 1000 2000 3000 4000 5000 6000 7000 8000 9000

time (sec)

com

pres

sion

(mm

)

0

20

40

60

80

100

120

140

160

180

200

load

(N)

displacement for 3 MPadisplacement for 2 MPaload for 3 MPaload for 2 MPa

removeradialconstraintload control

displacement control

spotwelding lid

PrePre--stressing pebble stacksstressing pebble stacks

After pre-stress

heated Pebble-stack

persen tot 3 MPa + holdtime

0

20

40

60

80

100

120

140

160

180

200

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

displacement (mm)

load

(N)

3 MPa test2 MPa test

XrayXray tomography of the pebble stackstomography of the pebble stacks

Xray tomography enhances the PIEXray tomography results could be used for thermo-mechanical models -> pebble size and location, number of contact point

Measurement of size distributionMeasurement of size distribution

Example from beryllium irradiation (HIDOBE)Pre-stress at 1 MPa, strain approx. 0.7%

11448 pebblesAv. Size 0.514 mm Roundness 1.12

1976 pebblesAv. Size 0.962 mm Roundness 1.12

OutlookOutlook

Loading of the specimensCharacterisation of the pebbles in December/JanuaryX-ray tomography January

Manufacturing irradiation rigStarted ordering components: some rare earth materials (Cd and Hf) have delivery times > 4 monthsFinal rig drawing are preparedDrum machining to start in December/JanuaryLoading of the drums and assembly February

Final design and safety report is in preparationAccount for HUE to LUE conversion and HFR operational requirements

Status of the high fluence irradiation of ceramic pebbles in the HICU projectOutlineObjectivesIrradiation characteristicsSpectrum effect in OrthosilicateSpectrum effect in MetatitanateTest MatrixCapsule designDesign of the irradiation capsuleLocation of the ceramic pebble stacksLocation of the ceramic pebble stacksCapsule designCadmium shield manufacturingThermal Design of HICUThermal Design of HICU (2)Thermal Design of HICU (3)Thermal Design of HICU (4)Cross section temperaturesCross section temperatures (2)Thermocouple distributionPre-stressing pebble stacksPre-stressing pebble stacksXray tomography of the pebble stacksMeasurement of size distributionOutlook

Documents

Pre-irradiation Characterization of Beryllium for High ...Boudewijn Pijlgroms a NRG Petten, the Netherlands Ceramic Breeder Blanket Interactions CBBI-13, 1 December. Outline Objectives