International Workshop on Liquid Metals Breeder Blankets23-24 September 2010

CIEMAT, Madrid, Spain

HCLL Test Blanket Module

Test program in ITER

Y. Poitevin, M. Zmitko, I. Ricapito, Fusion for Energy

From the contribution of L. Bühler (KIT), C. Mistrangelo (KIT),

L. Sedano (CIEMAT), C. Moreno (CIEMAT)

and the TBM Consortium of Associates

J.-F. Salavy

G. Aiello

A. LiPuma

M. Zmitko

Y. Poitevin

I. Ricapito

L. Bühler

C. Mistrangelo

L.V. Boccaccini (TBM-CA PL)

Forschungszentrum

Karlsruhein der Helmholtz-Gemeinschaft

F. Gabriel

G. Rampal

H. Simon

L. Sedano

C. Moreno

L. Batet

E. Mas de les VallsUPC

Presentation Layout

• Main HCLL TBM design features

• ITER experimental programme

• Magneto-hydrodynamics related

tests

• Tritium cycle related tests

HCLL Test Blanket Module

Manifolds

PbLi flow design

inlet

outlet

manifolds

breeder units

V PbLi ~1 mm/s

Adopted Strategy for the TBM

Programme Integration (IRP v2.0)

4 versions per each TBM are considered with

specific objectives as follow:

Learning/validation phase

the Electro Magnetic module (EM-TBM): H phase, H-He

phase;

the Thermal/Neutronic module (TN-TBM): D-phase;

DEMO-relevant data acquisition phase

the Neutronic/Tritium & Thermo-Mechanic module (NT/TM-

TBM): DT1 phase;

DEMO-relevant data acquisition phase (2nd 10 years)

the INTegral TBM (INT-TBM): DT2 (high duty, long pulses)

ITER Experimental ProgrammeComplete

Tokamak Core

First

Plasma

Hydrogen/ Helium

Phase Complete

Deuterium Phase

Complete

Start Torus PumpDown

First Plasma

Plasma Restart

Plasma Development, H&CD Commissioning, Diag, Control, TBMs

Full H&CD, H-modes, ELM Mitigation

D Plasmas on W-Divertor

DT Plasmas

CFC/W Divertor Changeout

TBMs

Full Heating capability

H-mode Studies (D)Trace-T Studies

Q=10 Q=10 Long Pulse

DT Hybrid

DT Non-inductive

T-Plant Commissioning

Tritium Introduction

~10% T-throughput

TBM Programme EM-TBM TN-TBM NT/TM-TBM INT-TBM

Blanket

Divertor

NBI 1+2

Diagnostics

Diagnostics

H-mode Studies (He)

Hydrogen Commissioning

Diagnostics

ECRH + ICRF

Nuclear authorization

TBMs

Nuclear readiness

MHDHCLL TBM test program in ITER

A complex MHD sensitive design

Electrical

flow coupling

Flow bending +

narrow gap

3D expansions/

contractions

Buoyancy

phenomena

Importance of MHD investigations in ITER

TBM

PbLi flow coupled phenomena:

- Corrosion

- Tritium permeation

- High Ha (B 4-5T)

- B (1/R)

- Btor + Bpol

- B (t)

Test conditions hardly

(not) attainable in another

facility

• Gaining knowledge about complex coupled physical phenomena

occurring in a fusion reactor environment (e.g. magneto-convection,

electromagnetic coupling)

broadening and confirming available results coming from smaller

experimental facilities

• Creating a data base of benchmarks to validate the various stages of

the ongoing development of numerical MHD codes

• Verifying and quantifying effects of stray magnetic field, electrical

disturbances and real working conditions on the instrumentation

• Collecting data and operating experience for applications of HCLL

blankets in a DEMO reactor

suggesting suitable design modifications for improved performance of

a DEMO blanket

Objectives of MHD experimental campaign in ITER

Forschungszentrum

Karlsruhein der Helmholtz-Gemeinschaft

Forced flow isothermal experiments (no plasma/no heat flux; EM-

TBM)

To Investigate separately MHD phenomena: there is no coupling to

heat transfer processes, where buoyancy may play an important role.

Data used to validate theoretical predictions of pressure drop and flow

distribution in the TBM.

Imposed heat flux in BUs (no plasma; EM-TBM): heated plates and

defined heat extraction through neighboring cooling plates

To study natural (buoyancy effects) and mixed convection. Outcomes

used to select and validate numerical models for magneto-convection.

Imposed thermal power and first wall heat flux (with plasma; NT-

TBM, IN-TBM)

To analyze coupled MHD and heat transfer phenomena under realistic

operating conditions (study of overall blanket performance)

Forschungszentrum

Karlsruhein der Helmholtz-Gemeinschaft

Main types of MHD experiments in ITER

Applicability of sensors in fusion LM blanket environment (T

550°C, strong magnetic field B, T and B gradients, flowing PbLi,

corrosion)

Material production/selection (max T and PbLi compatibility)

Quantification of thermoelectric and magnetic field effects required

Achievable measurement accuracy due to small velocities in ITER

TBM: signals are very small (influence of electromagnetic

disturbances)

Lack of space (design integration constraints)

Need to optimize number and size of sensors, to define proper

integration of instruments in the TBM (e.g. cable

arrangement…)

MHD flows with buoyancy effects and mixed convection

Global electromagnetic coupling for complex 3D flows

Complemen--

ary numerical

studies

Forschungszentrum

Karlsruhein der Helmholtz-Gemeinschaft

Open issues for MHD campaign in ITER

Illustration of invasiveness of MHD

instrumentation

TBM ½-scale mock-up

instrumented with potential

probes for test in KIT/MEKKA

facility)

– L. Bühler, C. Mistrangelo (FZK) et al., 2008

Tritium cycleHCLL TBM test program in ITER

HCLL TBM System Process Flow Diagram

Physical process/phenomena considered in the

HCLL TBS tritium-related models • EU (e.g. CIEMAT) has developed good, but not-yet-validated, predictive

tools used for conceptual design specifications

• TRICICLO code, TMAP7-code based model components/systems

models approach

Tritium breeding in LM

Tritium diffusion in PbLi taking into account MHD aspects

Tritium permeation from PbLi towards He coolant (through EUROFER structures)

He bubbles phenomena (e.g. Nucleation, Transport, Stability, Coalescence)

Tritium diffusion and transfer into He bubbles; tritium trapping

He coolant chemistry

Tritium extraction from PbLi

Gas-Liquid contactor technology

Permeator –based technology (e.g. Tritium permeation through α-Fe, PdAg)

He chemistry for Tritium Recovery System (TRS)

Molecular Sieves Bed (MBS) phenomena

Cold trap (CT) phenomena

Fundamental objectives for tritium cycle related tests in ITER

-

Determination of the tritium residence time in the HCLL and HCPB TBMs as

depending on operating parameters (e.g. T extraction efficiency, purge gas

chemistry)

Determination of the tritium permeation rate into the primary cooling system

(HCS) of both HCLL and HCPB-TBM as a function of the chemistry of the

He coolant

Determination of the ratio HTO/HT produced in the HCPB-TBM breeder

varying the purge gas chemistry

Determination of the TEU extraction efficiency as a function of the operating

conditions

chemistry of the stripping gas

temperature of the system

G/L ratio

These experimental objectives can be reached only if accurate tritium mass balances

can be performed. This requires a) reasonably low amount of tritium lost by parasitic

effects and b) good tritium accountancy.

Additional objectives under assessment for qualification of component/system models

H-H phaseHH- #1 Study of permeation phenomena as function of various parameters (e.g. LM

temperature, LM flow rate, MF, hydrogen injection, HCS chemistry)

HH- #2 Testing of CPS performance (e.g. effect of flow rate, hydrogen p.p., HCS chemistry)

HH- #3 Testing of TES (TEU+TRS) performance (e.g. LM) temperature, stripping gas flow

rates, stripping gas pressures, stripping gas H2-dopping)

HH- #4 Assessment of global hydrogen (or deuterium) residence time in HCLL TBS

D-D phaseDD-#1 Initial study of tritium breeding prediction vs local concentration measurements

DD-#2 Study of D/T transfers between various TBS

(TBM HCS CPS ISS/WDS, TBM TEU TRS ISS/WDS, )

DD-#3 First tritium tracking and global tritium residence time assessment at TBS system

with uncertainties

D-T phaseDT-#1 Further study of tritium breeding and tracking prediction vs local concentration

measurements

DT-#2 Study of T transfers between various TBS

(TBMHCSCPSISS/WDS, TBMTEUTRSISS/WDS )

DT-#3 Tritium tracking and global tritium residence time assessment at TBS system

with uncertainties

Open issues for HCLL Tritium cycle

related experimental program in ITER

Tritium sensors are the bottleneck of maximization of

Tritium experiments in ITER TBM

Intensive R&D is needed on:

– T sensor in PbLi

– T sensor in pressurized He

Understand He behaviour in PbLi and clarify the impact

of He bubbles on Tritium transport:

– Completion and detailed assessment of LIBRETTO

experiments (including PIE, benchmark modelling)

– Complementary Out-of-ITER tests (e.g. He micro/nano-

bubbles injection technological challenge)