Text optional: Institutsname � Prof. Dr. Hans Mustermann � www.fzd.de � Mitglied der Leibniz-Gemeinschaft

DRESDYN

A new platform

for liquid metal thermohydraulic studies

and measurement technique developments

Gunter Gerbeth, Sven Eckert,

Frank Stefani, Thomas Gundrum

Helmholtz-Zentrum Dresden-Rossendorf, Germany

FR13

Paris, France, March 6, 2013

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Background and Motivation of DRESDYN

• Important for SFR‘s:

� Measuring techniques for liquid sodium, visualization of installations

� Exp. data for code validation, e.g. for two-phase flows

� Exclusion of Na-water reactions by using „smart“ heat exchangers

• Experiments with liquid sodium related to the generation and

the action of cosmic magnetic fields� Precession driven dynamo experiment

� Tayler-Couette experiment for the combined study of the

Magnetoroational instability and the Tayler instability

• Renaissance of liquid metal cooled fast reactors in the

framework of the GEN IV initiative� Sodium-cooled fast reactor ASTRID (France, until 2020 ?)

� Lead-cooled transmutation machine MYRRHA (Belgium, until 2022)

⇒ EU projects CP-ESFR, ADRIANA, HELIMNET, THINS, ESNII+

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DRESDYN: General features

Features:

• New building ~ 500 m2

• Total sodium inventory: 12-15 tons

• Precession driven experiment with separate strong basement and containment for Argon flooding

• Big hall for SFR related experiments, including ISI, a sodium loop, X-ray lab

• Financing is given, construction will start soon in spring 2013

• First experiments 2015 (hopefullyA)

DRESDYN: DREsden Sodium facility

for DYNamo and thermohydraulic studies

A large-scale new infrastructure for liquid metal experiments

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DRESDYN: General scheme

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DRESDYN: Building

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Planned precession experiment:

• 2 m diameter, 2 m height,

8 m3 liquid sodium

• Rotation with 10 Hz, precession

with 1 Hz

• Magnetic Reynolds number ~ 700

• Water test experiments at scale 1:6

Precession (rotation around two axes) is considered as one (complementary) energy source of the geodynamo

Precession driven dynamo

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Precession driven dynamo: Containment and storage

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� Safety concept exists and is permanently extended

� Decision for a massive containment around precession dynamo

� Reaction in case of accidents: stop air supply, quickly flood with Argon

� In some special scenarios Argon must remain there for two days

Na-safety and handling

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� Storage with 3 large and several smaller tanks (appr. 13 tons of sodium)

� Provider: Metaux Speciaux

� Demand from fire protection: Storage must also be floodable with Argon

Na-safety and handling

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Essential basis:

New measurement technique developments

for liquid metal flows

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• A flow field modifies an external magnetic field:

B = B0 + b, b ~ Rm B0 (Rm = µσLv)

⇒⇒⇒⇒ the magnetic field measured outside the melt

contains information about the flow field

• gives in a robust way the 3D mean flow field every ~ 1s

• Application in industrial silicon crystal growth:

Contactless Inductive Flow Tomography (CIFT)

for liquid metal flows

Measuring coil

for CIFT

installed at

industrial

Cz facility

On-line mean flow monitoring demonstrated in industry

Permanent instrumentation, not just measurement

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CIFT at bubbly two-phase flow

Flow reconstruction in the mould from 2x7 fluxgate

sensors at the narrow faces:

Very intermittent two-phase flow behaviour

Transitions between

double and single

roll flows

CIFT resolves

between double and

single roll flow fields

Background: steel casting into mould with argon bubbles in nozzle

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CIFT at bubbly two-phase flow

Flow reconstruction in the mould from 2x7 fluxgate

sensors at the narrow faces:

Very intermittent two-phase flow behaviour

Transitions between

double and single

roll flows

CIFT resolves

between double and

single roll flow fields

Background: steel casting into mould with argon bubbles in nozzle

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Velocity measurements in Na

0,0 0,2 0,4 0,6 0,8 1,00,4

0,5

0,6

0,7

0,8

0,9

1,0

1,1

B = 0 T

B = 0.11 T

B = 0.21 T

B = 0.32 T

B = 0.51 T

B = 0.58 T

velo

city [m

/s]

channel width y / a

Mean velocity and turbulent fluctuations in a Na duct flow

Mean velocities measured by ultrasonics

Non-trivial flow caused by

an external magnetic field

turbulence spectra

measured by a local

potential probe

Velocity profile measured by Ultrasound Doppler Velocimetry (UDV)

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Contactless flow meter based on phase shifts

Contactless flow rate measurement

y

x

z

flow receiver coil1

receiver coil2

channelwall

emitter

coil

magnetic field

induced currents

Linear dependence of phase shift on the flow rate

Commercially available via company SAAS Ltd. Dresden

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Planned In-Service-Inspection experiment for SFR

Measuring techniques for liquid sodium

� Contactless inductive flow tomography

� Immersed magnetic flow rate sensors

� Ultrasonic techniques for velocity

� Ultrasonic techniques for positions

� Ultrasonic techniques for gas bubble detection

Objectives:

- flow rate sensor at primary pump model

- gas bubble injection

- natural convection in pool

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X-ray source

detector

liquid container

X-ray visualizations

attractive to study Na boiling or gas entrainment into Na

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200 mm

30

0 m

m

12 mm

30 mm

parallelepipedic vessel filled with GaInSn

nozzle: 0.5 mm i.d.

xy

z

X-ray visualization of bubbles in liquid metals

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X-ray visualization of bubbles

Argon bubbles in water (left) and GaInSn (right)

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X-ray visualization of gas bubble entrapment in liquid metal

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Self-excitation in SFR‘s ?

An old question relating SFR‘s with geo- and astrophysics: Is there a chance

for magnetic-field self-excitation in the helical flow of the core of an SFR?

?

Since 11 years, succesful dynamo experiments with liquid sodium (Riga, Karlsruhe, Cadarache)

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Self-excitation in SFR‘s ?

What happens when the austenitic steel in the core is replaced by

ferritic/martensitic (e.g. ODS) steels with high µr?

First 3D-simulations of two different

topologies of flow and high µr areas.

Significant reduction of the

critical magnetic Reynolds number!

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Summary

DRESDYN

- a new lab for liquid metal studies, in particular Na

- strongly based on new measurement techniques

- besides SFR also basic geo- and astrophysical experiments

- intended as a European platform

- first experiments (hopefully) in 2015...

Thank you!

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Gas bubbles in GaInSn

bottom injection at 2 orifices

X-ray visualization of bubbles in liquid metals