15th ITPA meeting on SOL/Div
1. Fuel removal (MD modeling)
2. Fuel removal
4. Dust芦川 直子（核融合研）

プラズマ物理クラスター スクレープオフ層とダイバータ物理サブクラスター会合
つくばサイエンスインフォメーションセンター
2011年7月20日

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1. Fuel removal (MD modeling) ： ７件

•K. Schmid“What can MD bring to PWI modelling ? “•Z. Yang” MD simulations of PWI at ASIPP”•Udo v. Toussaint “Hydrogen transport in tungsten”•Y Ferro “The Interaction of H/T with Be and C fromDensity Functional Theory calculation - Formation of mixed
Be/C materials”•Heinola “Hydrogen retention in W - A MultiscaleApproach”•N. Juslin “MD simulation of H and He defects in W”•F. Sefta “Modeling tungsten surfaces exposed to low-energy
He/H plasmas on extended time scales (beyond MD) “2

N. Juslin, : Surface modification
F. Sefta:Bubble
U.Toussaint ,Kalle Heinol:リテンションのモデリ
ング＆マルチスケール手法
3

U.Toussaint4

Z. Yang*Reflection behavior of C atoms on W surface52. Fuel removal ： ４件
•R. Doerner “Be flash heating”•V. Philipps “W flash heating”•J. Davis “D reabsorption by depleted codeposits”•M. Shimada “deuterium retention in neutronirradiated tungsten”

6Goal of the project is to investigate the effectiveness of various
heat pulses associated with radiative plasma termination, as ameans of tritium removal from Be codeposits in ITER.
A 50 J laser (@1064 nm) is used to vary the temperature of Be
codeposit formed in PISCES-B.

R. Doerner7w/o flash
w/ flash

Temp

R. Doerner8

W flash heating

V. Philipps

9V. Philipps

10V. Philipps

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J. Davis
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J. Davis
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*Neutron-irradiation at HFIR, ORNL

M. Shimada

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4. Dust : ５件•N. Ashikawa “Dust ejection experiment using sphere carbon
dust with different diameters in LHD”
•A.Litnovsky “First results of a new dust campaign atTEXTOR / DIIID “•S.H. Hong “Large size high velocity dust observed in KSTAR+ First experiment in TReD device (Transport and Removal
Experiment of Dust) Modification of CDG for dust detection”•S. Budaev “Dust generation in T-10 and QSPA + Dust
immobilization in tokamaks”•Volker Rohde “Dust investigations in AUG (collection,classification, comparison to lab measurements) “15Experimental setup for dusts ejection in LHD- A dust holder was installed from thebottom port.
- A high speed camera observed dusts
behaviors from the upper port to the 1m
dust holder at the bottom port.

Divertor plates
Divertor leg
manipulator
HolderField of view of the camera
Diameters of sphere carbon
dust are 8 and 120 micron

10 µm

The poloidal cross-section of LHD
at the holder position

Many ejected dusts have constant velocities up to 40 m/s(8 µm)Y Axis4500FPS

Velocity (m/s)

040

Velocity is not dependent on the theirdistances from the holder.

30

Direction of motion is limited.
Time of illumination for each particle
is less than 5ms.

20

100Holder

20

40

60

80

Y (pixel)

100120Starting points of illumination are not
140 the same. Only heated particles can17
be observed.

New 8 micron experiment : improvement of image’s
contrast
1)

2)

3)

(1) Direction of motion is unstable.

Position ofdust holder atlower port
Camera observed fromupper to lower(2) Direction of motion is limited.
(3) At different radial position,
remained dust particles (not ablated yet)were observed at different radialposition (red circle)

120 micron experiment : velocities are less than 20 m/s
Integrated intensities using
different frames30Direction of motion is limited.

Velosity (m/s)

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Typical illumination time is from 5 to10 ms

20
15

Depending on the sensitivity ofcamera detector

1050

Different dust particles
19Experiment description II in TEXTOR:
discharge scenario and dust types, 5th May 2011
Operated by A.Litnovsky<<Discharge scenario>> Identical NBI heated repetitive discharges;
 NBI 2, 1 MW, NBI 1 (first two units on first day); Counter-current and reversed Bt; Ip=350 kA; Bt=2.25 T;
dust launches for 1-3 discharges;

Spherical test limiterwith dust holder<<What is new>> Carbon spherical dust of different sizes: 8 um vs. 60 + 8 um (request from modeling) High resolution fast camera: Phantom v. 641, 4 MPix@ 5kframes/sec,max. 219 kframes/sec.
Installation/position

LHD

TEXTOR

Divertor plasma/lower

Limiter/upper

Dry powder

Wetted by ethanol(DIII-D type)

Initial condition

This work is being made under IEA-ITPA Joint Experiments Program, task DSOL 21,
IEA / TEXTOR collaboration

N. Ashikawa &A.Litnovsky

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A.Litnovsky

V. Rohde

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V. Rohde
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S. Budaev

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S. Budaev

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