Plasma shield dynamics under high-power plasma stream irradiation of target surface
The main aim of present work was analysis of plasma shield dynamics at the vicinity of target during the plasma stream irradiation.
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| Zitieren: | Plasma shield dynamics under high-power plasma stream irradiation of target surface / V.V. Chebotarev, I.E. Garkusha, V.A. Makhlaj, N.I. Mitina, D.G. Solyakov, V.I. Tereshin, S.A. Trubchaninov, A.V. Tsarenko, H. Wuerz // Вопросы атомной науки и техники. — 2000. — № 3. — С. 90-92. — Бібліогр.: 3 назв. — англ. |
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nasplib_isofts_kiev_ua-123456789-823722025-02-23T19:28:37Z Plasma shield dynamics under high-power plasma stream irradiation of target surface Chebotarev, V.V. Garkusha, I.E. Makhlaj, V.A. Mitina, N.I. Solyakov, D.G. Tereshin, V.I. Trubchaninov, S.A. Tsarenko, A.V. Wuerz, H. Рlasma Dynamics and Plasma-Wall Interaction The main aim of present work was analysis of plasma shield dynamics at the vicinity of target during the plasma stream irradiation. This work was partly supported by the Science and Technology Center in Ukraine (STCU), Grant #881, and Ministry of Education and Science of Ukraine, International Collaboration, Grant #2M/92-2000. 2000 Article Plasma shield dynamics under high-power plasma stream irradiation of target surface / V.V. Chebotarev, I.E. Garkusha, V.A. Makhlaj, N.I. Mitina, D.G. Solyakov, V.I. Tereshin, S.A. Trubchaninov, A.V. Tsarenko, H. Wuerz // Вопросы атомной науки и техники. — 2000. — № 3. — С. 90-92. — Бібліогр.: 3 назв. — англ. 1562-6016 https://nasplib.isofts.kiev.ua/handle/123456789/82372 533.9 en Вопросы атомной науки и техники application/pdf Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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DSpace DC |
| language |
English |
| topic |
Рlasma Dynamics and Plasma-Wall Interaction Рlasma Dynamics and Plasma-Wall Interaction |
| spellingShingle |
Рlasma Dynamics and Plasma-Wall Interaction Рlasma Dynamics and Plasma-Wall Interaction Chebotarev, V.V. Garkusha, I.E. Makhlaj, V.A. Mitina, N.I. Solyakov, D.G. Tereshin, V.I. Trubchaninov, S.A. Tsarenko, A.V. Wuerz, H. Plasma shield dynamics under high-power plasma stream irradiation of target surface Вопросы атомной науки и техники |
| description |
The main aim of present work was analysis of
plasma shield dynamics at the vicinity of target during
the plasma stream irradiation. |
| format |
Article |
| author |
Chebotarev, V.V. Garkusha, I.E. Makhlaj, V.A. Mitina, N.I. Solyakov, D.G. Tereshin, V.I. Trubchaninov, S.A. Tsarenko, A.V. Wuerz, H. |
| author_facet |
Chebotarev, V.V. Garkusha, I.E. Makhlaj, V.A. Mitina, N.I. Solyakov, D.G. Tereshin, V.I. Trubchaninov, S.A. Tsarenko, A.V. Wuerz, H. |
| author_sort |
Chebotarev, V.V. |
| title |
Plasma shield dynamics under high-power plasma stream irradiation of target surface |
| title_short |
Plasma shield dynamics under high-power plasma stream irradiation of target surface |
| title_full |
Plasma shield dynamics under high-power plasma stream irradiation of target surface |
| title_fullStr |
Plasma shield dynamics under high-power plasma stream irradiation of target surface |
| title_full_unstemmed |
Plasma shield dynamics under high-power plasma stream irradiation of target surface |
| title_sort |
plasma shield dynamics under high-power plasma stream irradiation of target surface |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2000 |
| topic_facet |
Рlasma Dynamics and Plasma-Wall Interaction |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/82372 |
| citation_txt |
Plasma shield dynamics under high-power plasma stream irradiation of target surface / V.V. Chebotarev, I.E. Garkusha, V.A. Makhlaj, N.I. Mitina, D.G. Solyakov, V.I. Tereshin, S.A. Trubchaninov, A.V. Tsarenko, H. Wuerz // Вопросы атомной науки и техники. — 2000. — № 3. — С. 90-92. — Бібліогр.: 3 назв. — англ. |
| series |
Вопросы атомной науки и техники |
| work_keys_str_mv |
AT chebotarevvv plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT garkushaie plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT makhlajva plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT mitinani plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT solyakovdg plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT tereshinvi plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT trubchaninovsa plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT tsarenkoav plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface AT wuerzh plasmashielddynamicsunderhighpowerplasmastreamirradiationoftargetsurface |
| first_indexed |
2025-11-24T16:21:23Z |
| last_indexed |
2025-11-24T16:21:23Z |
| _version_ |
1849689409471905792 |
| fulltext |
UDC 533.9
Problems of Atomic Science and Technology. 2000. N 3. Series: Plasma Physics (5). p. 90-92 90
PLASMA SHIELD DYNAMICS UNDER HIGH-POWER PLASMA
STREAM IRRADIATION OF TARGET SURFACE.
Chebotarev V.V., Garkusha I.E., Makhlaj V.A., Mitina N.I., Solyakov D.G., Tereshin V.I.,
Trubchaninov S.A., Tsarenko A.V. and H.Wuerz*
Institute of Plasma Physics of the National Science Center “Kharkov Institute of Physics and
Technology”, Akademicheskaya St. 1, 61108 Kharkov, Ukraine,
*)Forschugszentrum Karlsruhe, IHM, Postfach 3640, D-76021, Karlsruhe, Germany.
High-power quasi-steady-state plasma stream was
applied for current disruption simulation in ITER
tokamak and testing divertor materials. Plasma
shielding layer was formed during the high-power
plasma stream interaction with the target surface.
The main aim of present work was analysis of
plasma shield dynamics at the vicinity of target during
the plasma stream irradiation. High-power plasma
stream was generated by powerful quasi-steady-state
plasma accelerator QSPA Kh-50 [1] and injected into
longitudinal magnetic field with strength up to 1T.
Plasma stream parameters in place of target position
were follows: average electron density (2-4)⋅1016 cm-3,
maximum power density up to 20 MW/cm2, maximum
proton energy 200 eV, pulse duration 150-170 µs,
average β≈(0,1÷0,2) [2]. Graphite targets with diameters
5, 13 and 22 cm were used.
1. Analysis of energy of plasma flowing
around the target
Experiments were performed in magnetic field
Bz0=0.54 T. Energy density distributions in the free
plasma stream, in the plasma shield and behind the
targets were measured by copper local movable
calorimeter with diameter 5 mm. The scheme of
experiment is shown in fig.1.
We assumed that shielding effects at the process of
measurements by local calorimeter are the same for both
cases with and without targets and for different target
diameters. One can see from fig.2 that the radial
distribution of energy density in free plasma stream is
symmetrical. The value of ∫= dSrQ w )(ρ in a free
plasma stream is equal 53 kJ (no correction for
calorimetric measurements in magnetic field was done).
Unsymmetrical distributions of energy density behind
the target (fig. 3, 4 and 5 (g)) can be explained by
influence of target supporting bar on the results of
measurements as far as calorimeter was moving behind
.
supporting bar. The local minimum at the vicinity of the
axis was observed for all radial distributions of plasma
-50 -40 -30 -20 -10 0 10 20 30 40 50
0
2
4
6
8
10
12
14
16
Q=35 kJ
Target diameter 5 cm
ρρ w
, J
/c
m
2
R, cm
Fig.1. The scheme of experiment
- 5 0 - 4 0 - 3 0 - 2 0 - 1 0 0 1 0 2 0 3 0 4 0 5 0
0
5
1 0
1 5
2 0
2 5
3 0
ρρ
w
, J
/c
m
2
R, cm
Fig.2.Energy density radial distribution
in free plasma stream. Magnetic field
H=0.54T.
-50 -40 -30 -20 -10 0 1 0 2 0 3 0 4 0 5 0
0
2
4
6
8
1 0
Q=30 kJ Target diameter 13 cm
ρρ w
, J
/c
m
2
R, cm
Fig.4. Energy density radial distribution
behind the target. Magnetic field H=0.54T.
Fig.3. Energy density radial distribution
behind the target. Magnetic field H=0.54T
91
energy measured behind the targets. For estimation of
the total energy of plasma, flowing around the targets,
Fig.5. Energy density radial distribution behind
the target. Magnetic field H=0.54T.
the energy density profiles were approximated by
symmetrical curves (fig. 3, 4 and 5(n)). In this case the
values of ∫= dSrQ w )(ρ estimated behind the targets
were 35 kJ for target diameter ∅ = 5 cm, 30 kJ for ∅ =
13 cm and 12 kJ for ∅ = 22 cm correspondingly.
The total plasma energy measured behind the targets
with different diameters normalized by total energy in
free plasma stream as a function of target diameter are
presented in fig 6. As we can see from this figure, the
ratio Qbehind target/Qfree plasma stream is decreased with
increasing the target radius from 0.6 (for target diameter
5 cm) till 0.2 (for target diameter 22 cm).
It follows from fig. 6 that up to 50-60 % of incident
plasma stream energy flows around the target placed in
magnetic field Bz0 = 0.54 T. As we can see from those
experimental results plasma flows around the targets
and doesn’t move to the axis.
The radial distribution of energy density in a free
plasma stream without magnetic field is symmetrical
fig.7. The value of ∫= dSrQ w )(ρ in a free plasma
stream is equal 66 kJ. The distributions of energy
density in plasma stream without magnetic field behind
the target also symmetrical (fig. 8 (g)) and local
minimum of energy density feebly marked. In magnetic
field Bz0 = 0.36 T the distribution of energy density
behind the target is unsymmetrical (fig. 8(�)) and can be
explained by influence of target supporting bar.
Without magnetic field about 80-85% of incident
plasma energy flow around the target (fig.8). In this
case (Bz0 = 0) plasma, flowing around the target, moves
to the axis behind the target (the local minimum in
energy density distribution at the vicinity of the axis
was not observed). Local maximum of energy density
behind the target was observed. This maximum moved
outward the axis with increasing the target diameter.
2. Electron temperature and electron density
in plasma shields.
Electron temperature was evaluated on the base of
measurements of the ratio of CIII and CII spectral lines
intensities. The monochromator MDR 6 of Russian
trade mark with photomultiplier as a recorder was used
for carbon lines intensities measurements. Spatial
resolution was about 5 mm in radial and axial
directions. Intensities of spectral lines were measured
for different distances from the target surfaces.
Electron density was measured by using Stark
broadening of Hβ spectral line. High-speed photo
camera was used for radiation recording. Spatial
-50 -40-30 -20-10 0 10 20 30 40 50
0
1
2
3
4
5 Q=12 kJ Target diameter 22 cm
ρρ w
, J
/c
m
2
R, cm -50 -40 -30 -20 -10 0 10 20 30 40 50
0
10
20
30
40
50
60
R, cm
ρρ w
, J
/c
m
2
Fig.7.Energy density radial distribution in
free plasma stream. Magnetic field H=0.
-50 -40 -30 -20 -10 0 10 20 30 40 50
0
5
10
15
20
25
R, cm
ρρ w
, J
/c
m
2
Fig.8. Energy density radial distribution behind
the target. � - magnetic field H=0;� -magnetic
field H=0.36 T.
0 2 4 6 8 10 12
0,0
0,2
0,4
0,6
0,8
Q
be
hi
nd
ta
rg
et
/Q
fr
ee
p
la
sm
a
st
re
am
Target radius, cm
Fig.6. Total energy measured behind the
targets with different diameters normalized on
total energy in free plasma stream as function
of target diameter.
92
resolution in radial direction was about 1-2 mm and in
axial direction 8-10 mm.
Typical waves forms of CIII and CII spectral lines
are shown in fig. 9.
Numerical results, presented in [3] were used for
electron temperature estimation in plasma shield.
The distributions of electron temperature and
electron density along the axis, evaluated from
experimental data, are shown in fig. 10 and 11.
As one can see the electron temperature, evaluated
by ratio CIII/CII carbon spectral lines intensities,
weakly depends on target diameter and equals (2-2.5)
eV for both targets and for distances up to 20 cm from
the target surface.
Plasma shield densities are comparable for targets
with diameters 5 cm, 13 cm and 22 cm. Close to the
target surface the electron density was equal (2-3)x1017
cm-3. But at the vicinity of (2-3) cm from the surface it
was decreased down to 9x1016 cm-3 for both targets with
diameter 5 cm and 13 cm. While the plasma density
close to the target with diameter 22 cm weakly depends
on distance from the target and equals (1-3)x1017 cm-3.
At the distances from the target more than 10 cm the
electron density was weakly decreased down to 4x1016
cm-3 at the distance (25-30) cm from the target surface.
This value was comparable with the density of
incident plasma stream. Thus the thickness of shielding
layer at vicinity of the sample with diameter a 5 cm was
10-15 cm and close to sample with diameter 22 cm was
25-30 cm.
3. Conclusions.
On the base of presented experimental results one
can conclude that plasma shield dynamics and its
parameters are strongly depended on target size.
The plasma flow around the target was observed.
Part of incoming plasma stream and plasma shield flows
around the target. Total value of energy, measured
behind the target was about (50-60)% of energy of
incoming plasma stream in magnetic field 0.54 T and
about 80-85% without magnetic field.
The plasma density value in shielding layer was by
one order of magnitude higher to compare with plasma
density value in a free plasma stream and depended on
size of target.
The thickness of shielding layer was 10-15 cm for
target diameter 5 cm and increased up to 25-30 cm with
increasing the target diameter up to 22 cm.
The value of electron temperature, measured by ratio
of intensities of CIII and CII spectral lines, was about 2 -
2.5 eV and practically not depended on target diameter
and distance from the target surface.
This work was partly supported by the Science and
Technology Center in Ukraine (STCU), Grant #881, and
Ministry of Education and Science of Ukraine,
International Collaboration, Grant #2M/92-2000.
References
[1]. O.S.Pavlichenko, V.I.Tereshin, V.V.Chebotarev
et. al., // Plasma Devices and Operations, Vol. 2,1992,
pp.155-165.
[2]. V.I.Tereshin, V.V.Chebotarev, H.Wuerz at al. //
Problems of Atomic Science and Technology. Series
«Plasma physics» 3(3) , 4(4), 1999, ð. 194 .
[3]. Hans R. Griem Plasma spectroscopy. Moscow.
«Atomizdat», 1969.
0 100 200 300 400
0
10
20
30
40
CII
CIII
P=20 MW/cm 2;
B
z0
= 0.54 T;
C
ar
b
on
li
n
es
in
te
n
si
ti
es
, a
.u
.
t, µµs
0 5 10 15 20 25 30
0.0
0.5
1.0
1.5
2.0
2.5
3.0
P=20 MW/cm
2
;
B
z0
= 0.54 T;
Distance from the target, cm
E
le
ct
ro
n
te
m
pe
ra
tu
re
, e
V
Fig.10. Electron temperature distribution along the
axis. � - target diameter 5 cm; � - target diameter
13 cm.
Fig.11. Electron density distributions along the
axis.
0 5 10 15 20 25 30
1017
1016E
le
ct
ro
n
de
ns
ity
, c
m
-3
Distance from the target, cm
Diameter of target 5cm
Diameter of target 13cm
Diameter of target 22cm
Fig.9. Time evolution of CII and CIII spectral lines
at the distance of 7 cm from the t arget surface with
diameter 13 cm.
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