New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR
This paper reviews the present status of new developments in ICRF antennas, recent results on more realistic modeling of ICRF antennas using the 3-D full electromagnetic code ICANT and, finally, the latest development in the scenarios of non-traditional applications of HF power for wall conditioning...
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| Veröffentlicht in: | Вопросы атомной науки и техники |
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2002
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| Zitieren: | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR / A. Lyssoivan, A. Messiaen, R. Koch, F. Durodié, G.S. Amarante-Segundo, P. Dumortier, D. Van Eester, M. Vervier, R. Weynants, H.G. Esser, E. Gauthier, F. Hoekzema, V. Philipps, E. Westerhof // Вопросы атомной науки и техники. — 2002. — № 4. — С. 24-28. — Бібліогр.: 15 назв. — англ. |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1859614401814855680 |
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| author | Lyssoivan, A. Messiaen, A. Koch, R. Durodié, F. Amarante-Segundo, G.S. Dumortier, P. Van Eester, D. Vervier, M. Weynants, R. Esser, H.G. Gauthier, E. Hoekzema, F. Philipps, V. Westerhof, E. |
| author_facet | Lyssoivan, A. Messiaen, A. Koch, R. Durodié, F. Amarante-Segundo, G.S. Dumortier, P. Van Eester, D. Vervier, M. Weynants, R. Esser, H.G. Gauthier, E. Hoekzema, F. Philipps, V. Westerhof, E. |
| citation_txt | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR / A. Lyssoivan, A. Messiaen, R. Koch, F. Durodié, G.S. Amarante-Segundo, P. Dumortier, D. Van Eester, M. Vervier, R. Weynants, H.G. Esser, E. Gauthier, F. Hoekzema, V. Philipps, E. Westerhof // Вопросы атомной науки и техники. — 2002. — № 4. — С. 24-28. — Бібліогр.: 15 назв. — англ. |
| collection | DSpace DC |
| container_title | Вопросы атомной науки и техники |
| description | This paper reviews the present status of new developments in ICRF antennas, recent results on more realistic modeling of ICRF antennas using the 3-D full electromagnetic code ICANT and, finally, the latest development in the scenarios of non-traditional applications of HF power for wall conditioning.
|
| first_indexed | 2025-11-28T17:05:33Z |
| format | Article |
| fulltext |
NEW DEVELOPMENTS IN ICRF ANTENNAS AND NON-
TRADITIONAL APPLICATIONS OF HF POWER ON TEXTOR
A.Lyssoivan1, A.Messiaen1, R.Koch1, F.Durodié1, G.S.Amarante-Segundo1, P.Dumortier1,
D.Van Eester1, M.Vervier1, R.Weynants1, H.G.Esser2, E.Gauthier3, F.Hoekzema2, V.Philipps2,
E.Westerhof4
1 Laboratoire de Physique des Plasmas / Laboratorium voor Plasmafysica, ERM/KMS, Association EURATOM-
BELGIAN STATE, 1000 Brussels, Belgium*
2 Institut für Plasmaphysik, Forschungszentrum Jülich, Association EURATOM-KFA, 52425 Jülich, Germany*
3 Association EURATOM-CEA sur la Fusion Contrôlée, CEA Cadarache, 13108 St Paul lez Durance, France
4 FOM-Instituut voor Plasmafysica 'Rijnhuizen', Associatie EURATOM-FOM, 3430 BE Nieuwegen,
The Netherlands*
* - Partners in the Trilateral Euregio Cluster (TEC)
Abstract
This paper reviews the present status of new
developments in ICRF antennas, recent results on more
realistic modeling of ICRF antennas using the 3-D full
electromagnetic code ICANT and, finally, the latest
development in the scenarios of non-traditional
applications of HF power for wall conditioning.
1. Antenna developments
The ICRH system installed on TEXTOR consists of two
double strap shielded or unshielded antennas, each fed
by a 2MW generator (in the frequency band 25÷38MHz)
via a transmission line [1,2]. Each antenna pair may be
operated in 0 or � phasing.
New developments on ICRH antennas are being
performed (i) to increase their RF voltage stand-off and
(ii) to solve the problem of generator tripping with fast
variation of antenna plasma loading. These innovations
were undertaken with a view to testing solutions to
increase the power capability and to decrease the
sensitivity to ELM’s of the ICRF system needed for
ITER. In addition to the antenna design activity,
development of the new RF diagnostic based on RF
probe arrays has been undertaken with the aim of
detecting (i) RF voltage/current at the antenna and (ii)
RF field in the scrape-of-layer along the torus.
1.1. Low Electric Field ICRF Antenna
To achieve the first goal (an increase of the antenna RF
voltage stand-off), the thin radiating straps (having a
thickness of 10 mm at the edges) of one of the two pairs
of TEXTOR antennas was replaced by a set of three
parallel cylindrical tubes of 30 mm diameter [3] (Fig.1).
Fig.1. The view of two types radiating elements
designed for the TEXTOR ICRF antennas:
standard thin strap (in the middle) and a new
design of three parallel tubes.
The driving idea for the test was to investigate if the
limits in voltage stand-off of an ICRF antenna were
determined by the voltage or by the electric field on the
edges of the inner conductors. A 2-D electrostatic
modeling [3] was used to analyze the original thin (T)
antenna and the new low electric field (LE) antenna. The
effect of the plasma was approximated by a conducting
plane in front of the radiating elements. The modeling
showed (Fig.2) that for the same voltage VA applied to
both antennas the maximum electric field (i) appeared at
the edges of the radiating elements and (ii) was reduced
by a factor of ~1.6 for the LE antenna.
Original ÒTÓ antenna
New ÒLEÓ antenna
Fig.2. Modeling of the electric field radiated by
one half of the original “T” and new “LE”
antennas. In each case, the amplitude of the RF
field is normalized to its maximum value.
As the RF current density is larger at the inner side of the
radiating strap [4] there is a loss of coupling to the
plasma (which can be expressed by the distributed
loading resistance RA) and a decrease of its distributed
inductance LA. For the given radiated power
2
AAARF )2(1 VGP =− , the antenna conductance may be
written as [1]:
( )( ) ( ) ( )AA1AAA LRlflLlRG ωβω <<= ,2 (1)
Here ( ) ( ) ( )( ) ( )l2sinl2l2sin1llf 22 βββββ +=1 ; l is the
length of radiating strap in the poloidal direction;
AACL2 ωλπβ == ; CA is the distributed capacitance.
When 41l0 << λ , function f1 has a small variation in
the relevant range (1.0 < f1 < 1.23) and can be considered
roughly as a constant. As a result, one can obtain from
(1) that, for the LE antenna, some of the decrease in RA
is compensated partially by a decrease of LA (GA-LE ≈
70RA-LE µOhm-1 for the LE antenna and GA-T ≈ 53RA-T
µOhm-1 for the thin one). Figure 3 compares the
(a)
(b)
(b)
(a)
evolution of RA with the plasma edge density for the two
antennas in the same set of discharges. The ratio RA-LE /
RA-T ≈ 0.68 and, for the same radiated power, we have
VA-LE / VA-T ≈ 1.06.
RA,LE
RA,T
(Ohm/m)
12
8
4
0
0
4
8
0 1 2 3 4
(Ohm/m)
> 4
< 9
> 9
< 13
> 13
< 17
> 17
< 22
V (kV)A
ne,40 (10 m )19 -3
Fig.3. The distributed loading resistance RA vs.
line averaged density near the plasma edge (at
6 cm from LCMF) analyzed for the TEXTOR
shots ##91409-91445.
The LE and T antennas have been routinely operated
with high reliability up to the full installed power (2MW
applied to each antenna, 95% of which were radiated).
No limit in the RF voltage stand-off for both antennas
has been noted so far. However, if the power limitation
is assumed to be due to arcing between the strap and the
antenna box one could expect an improvement in the RF
power handling capability of the LE antenna by a factor
2.32
LEATA
2
LEATATALEA ≈= −−−−−− )()
~~
( VVEEPP .
1.2. Load insensitive ICRF Antenna
The other new ICRF antenna system has been designed
(i) to be compatible with the inlet of the diagnostic
neutral beam between its two radiating straps (due to the
rearrangement of the diagnostic positions resulting from
the Dynamic Ergodic Divertor installation on TEXTOR)
and (ii) to be able to test a "conjugated T" mode of
operation [5] that is foreseen for the new JET-ITER-like
antenna [6]. The major problem of the ICRF heating of
plasma in the Elmy H-mode (the basic regime for ITER)
is the severe power limitation due to generator tripping
which occurs in presence of ELM’s. This tripping
happens due to fast increase of the antenna load by the
ELM’s or to arcs induced by them [7]. The "conjugated
T" mode is characterized by its insensitivity to the
variations of the antenna loading resistance and would
help to solve the problem of generator tripping.
The side and top view of the new antenna pair is shown
on Fig.4. The two identical radiating straps (part A-C on
Fig. 4a) are fed by their feeding lines at a tap B. They are
short-circuited at one side and connected at the other
side to a vacuum variable capacitor (grounded in E) by
means of a section C-D of coaxial line. The two feeding
lines are connected to the line coming from the generator
by means of a T junction as shown schematically on
Fig.5a). The lengths BR-T and BL-T between each tap
and the point “T” can be adjusted by means of the line
stretchers (LS)R and (LS)L.
Transmission line theory analysis. The antenna set-up
(Fig.5a) is easily modelled using transmission line
theory: (i) the radiating strap by sections of lossy strip
line characterized by distributed resistance (due mainly
to plasma loading) RA, inductance LA and capacitance
CA, (ii) the vacuum or air pressurized parts C-D and B-T
by sections of coaxial lines of appropriate characteristic
impedance, (iii) the capacitor CP by its capacitance and
stray inductance. The behaviour of this tuneable system
can be understood in terms of equations of a simplified
equivalent circuit (Fig.5b).
A
B
C
D E
B'
R
L
Fig.4. The side (a) and the top (b) views of the
new antenna pair. The top view shows the
upper part of the antenna on the R side and the
lower part on the L side, respectively.
DCBA C
E
R
PR
R
R
RR
DCBA C
E
L
PLL
L
LL
(LS)
(LS)
T
B'
B'
R
L
R
L
GENERATOR
R
L
C
B
D
A E
Fig.5. The schematic diagram of the load
insensitive antenna system (a) and the
equivalent circuit of the tunable strap (b).
For the frequency range used (f ≥ 30 MHz), the line path
A-D has an electrical length shorter than a quarter
wavelength λ/4 and behaves as an inductance L. The part
A-E of the antenna system is equivalent to a parallel
resonating circuit fed in B at the fraction α of this
inductance. We have R ∝ RA (R=RAlA-C in the limit of
short electrical length lA-D), L depends on LA (LA is a
weak function of the plasma loading [1]) and C is
determined by CP and its stray inductance. The
impedance seen in the point B is given by:
1)()2))(1(( 12
B >>∆−= − QffQiCRLZ ,α (2)
Here f is the operating frequency;
PCfff −=∆ ;
( ) 21
PP
−= LCfC
and RLfQ π2= . At the position B’ along
the feeder, which is at the distance λ/4 from the tap B,
the normalized impedance may be written as:
B00BB '' ZZZZixrz ==+= . (3)
Here LRCZr 2
0 α= ; ffQrx ∆= 2 and 0Z is the feeder
characteristic impedance. These relations are valid for
the right R and the left L straps. We have also zTR=zB’R
and zTL=zB’L, when the electrical lengths 2TRB' λnl =−
and 2TLB' λml =− are equal to integer numbers of the
half wavelengths.
Antenna matching conditions. The normalized
admittance in the point T (Fig.5a) seen from the
generator is given by:
TLTRT yyibgy +=+≡ , (4)
where LR ggg += and LR bbb += . The same power is
radiated by two straps when gR=gL (i). The generator
sees a matched load when yT =1, i.e. when bR= -bL (ii)
and 1LR =+= ggg (iii). If we choose CPR and CPL such
that zB’R≅z*B’L ,i.e. xR =-xL ≡ x, we satisfy the conditions
(i) and (ii) and we have 1
T ))(1(12 −+=≅ 2ζζ xgy with
xr=ζ . If additionally |x|≅1 the matching is obtained for
|ζ|=1 (condition (iii) is satisfied). These matching
conditions are fulfilled when:
1)(2 1 ±=∆== −ffQxrζ , (5)
12
0 == LRCZr α . (6)
The conditions (5) and (6) can be achieved
approximately by the proper choice of CPR and CPL and
of the tap position (i.e. by the value of α) for the
reference value A00 RRR ∝= , where fLR ∆= π40
. In this
case conditions close to matching will remain in a large
R or RA range around R0 or RA0 due to the small variation
of the function 2ζ/(1+ζ2) around ζ=1. The voltage
standing wave ratio (VSWR) remains low, S<1.5, in a
large range of antenna loading 0.38<RA/R0<2.6. This
large independence of the matching on RA has a
drawback. The phase difference φ∆ between the current
in two adjacent straps strongly depends on RA through
the relation ( ) ( )πζφ nm −+≅∆ 12arctg . Modeling of the
complete set-up is shown in Figure 6.
0 5 10 15 20
1
1.2
1.4
1.6
1.8
0 5 10 15 20
-1
-0.5
0
0.5
1
0 5 10 15 20
0
50
100
150
200
0 5 10 15 20
0.8
0.9
1
1.1
1.2
S
R(MW)P
P (MW)L
gR
g
bR
bL
( Ohm/m)AR
( Ohm/m)AR
( Ohm/m)AR
( Ohm/m)AR
L
∆φ [degree]
Fig.6. The result of optimization of the
“conjugated T” mode of operation for the case
of TEXTOR (CPR=80.4 pF, CPL=67.2 pF,
=λT-BRl 1.248, =λT-BLl 1.717, f=32.5 MHz).
The VSWR at the generator, S, remains below 1.1 in the
loading resistance range RA≈2.5÷9.5 Ohm/m and S<1.5
in the range RA≈1.6÷16.0 Ohm/m. It should also be
noted the following outcomes of the antenna matching
optimization for operation in the “conjugated T” mode:
- the normalized admittance remains close to conjugated
one (yTR≅y*TL) in the low S range;
- the normalized conductance remains very close to 0.5
(gR≅gL≅0.5);
- the radiated power becomes balanced in the straps
when gR=gL;
- the phase shift between the straps changes in the small
range φ∆ ≈110°÷140° for a roughly doubled variation of
the antenna-plasma resistance, observed in the
experiment, RA-T ≈6.0÷12.0 Ohm/m, (Fig.3), if
difference in the electrical length of the straps is equal to
half a wavelength, m-n =1.
2. ICRF Antenna modeling
More realistic antenna modeling using the 3-D full
electromagnetic RF code ICANT [4,8] has been
undertaken (i) to analyze the ICRF antenna near-field in
vacuum and (ii) to assess the antenna coupling capability
as a function of the current strap thickness and position
in an antenna box. This code computes the current
distribution on a 3-D model of ICRF antenna self-
consistently by superposing currents on each rectangular
element of the antenna model and imposing the
vanishing of the tangential electric field on the antenna
surface. Improvements in the ICANT code have been
done to allow more complicated modeling of ICRF
antennas surrounded by antenna box, with finite
thickness of the current straps and Faraday shield (FS).
The electromagnetic problem solved in the vacuum
region is matched with a surface impedance matrix
calculated by a full-wave code as a boundary condition
on the plasma-vacuum interface.
2.1. Analysis of the antenna near RF field in vacuum
A study of the antenna near field in vacuum is an
important issue particularly in relation to optimization of
the performance of ICRF wall conditioning discharges in
fusion devices using conventional ICRH antennas with
or without FS [9]. It is well known, that (i)
electromagnetic waves in the ICRF band are not
propagating in vacuum and that (ii) mainly the antenna
parallel electric RF field ˜ E z (along the static magnetic
field lines) is responsible for the neutral gas breakdown
and initial ionization by e-impact [10]. In general, ICRH
antennas with the radiating straps oriented in poloidal
direction can generate an ˜ E z -field in vacuum due to (i)
RF voltage difference between the strap and the
sidewalls and (ii) RF voltage induced between the tilted
FS bars by the time-varying magnetic flux [9]. ICANT
modeling of the antenna field in vacuum for the cases of
TEXTOR-like unshielded antenna and that one without
protecting box is shown in figures 7, 8. It is clearly seen
that the ˜ E z -field (i) is generated efficiently in both
analyzed cases and (ii) is localized at the edges of the
radiating straps. For the given RF current in the feeding
points, IRF =1 kA, the radial decay length of the field was
found to be larger in the hypothetical “no box” case
(Fig.8). Obviously it resulted from the absence of image
currents on the surfaces of former nearby located
antenna box. The conducting back-wall was present at
the same distance from the straps for both cases.
2.2. Antenna coupling analysis
The possibility to model thick antenna straps has been
recently implemented in the ICANT code. This
(a)
(b)
(a)
(b)
(a)
(b)
modification allows assessing more realistically the flow
pattern of the current on the main conductors of the
antenna. The main effect, which was investigated for the
first time in modeling of the JET-ITER-like ICRF
antenna [4], is the following. When increasing the
thickness of antenna strap, a larger fraction of the RF
current “prefers” to flow on the backside of the strap,
thereby reducing the current on the front side and
therefore decreasing the antenna-plasma coupling.
0
0.2
0.4
0 0.20 0.2
Z [m]
Y
[
m
]
-0.2
-0.4
-0.2
-0.1-0.2
Im Ez [kV/m]
75
50
25
-75
-50
-25
0.1 0.2 Z [m]
Fig.7. Modeling of the TEXTOR unshielded
antenna (f=32.5 MHz, �-phasing): (a) – the RF
current distribution in the straps and boxes; (b)
– toroidal distribution of the ˜ E z -field at the
coordinates: x=0.06 m; y=-0.15 m.
0
0.2
0.4
0 0.20 0.2
-0.4
-0.2
-0.2
Z [m]
Y
[
m
]
50
100
-50
-100
Im Ez [kV/m]
Z [m]-0.1-0.2 0.1 0.2
Fig.8. The simplified model of radiating straps
of the TEXTOR antenna without box (input
parameters are mentioned in Fig.7).
Modeling of the two types TEXTOR antenna radiating
elements (Fig.1) resulted in the following. The three-
tube radiating element (Fig.9a) caused the RF current to
re-distribute towards the backsides and, partially, to the
lateral sides (Fig.9b) due to larger thickness, thus
reducing antenna coupling by ~12%. On the other hand,
the discreteness of the tubes resulted in a more
homogeneous (by ~35%) RF current distribution in the
z-direction, compared with that of the standard strap,
where nearly all the current flows at the strap edges.
0.10
0
0.2
-0.2
0.4
-0.4
-0.05 0.050
Y
[
m
]
Z [m]Y [m]
0
0 100 200 300 400 500
0.5
1.0
1.5
2.0
2.5
0
Irf element indexes
Ir
f
[
kA
] tube front sides
tube backsides
short circuit
feeder
tube lateral sides
Fig.9. The model of single three-tube radiating
module of the TEXTOR LE antenna (a) and the
RF current distribution for each element of the
model (b) loaded by TEXTOR-like plasma:
ne0= 4.0×1019 m-3, nea= 1.0×1019 m-3, λne= 1.0
cm.
2.3. JET-ITER-like antenna modeling
Being in charge to build JET-ITER-like ICRF antenna
with the aim to demonstrate the feasibility of high power
density coupling, the Laboratory for Plasma Physics
ERM/KMS made also crucial contribution into a more
realistic modeling of this antenna using the ICANT code.
A self-consistent solution of the electromagnetic
problem in vacuum together with an input surface
impedance matrix for the realistic 3-D antenna geometry
revealed several major effects, like reduction of the
coupling due to radiating strap thickness and poloidal
phase difference between the straps, strong sensitivity of
the coupling to antenna-plasma distance and central
plasma density variations [4,6,8].
3. ICRF wall conditioning technique development
In future reactor-scale superconducting fusion devices
such as ITER, the presence of permanent high magnetic
field will prevent the use of Glow Discharge
Conditioning procedures in between shots, which
presently is the preferred method to decrease the content
of light impurities such as oxygen and to control the
recycling properties of the Plasma Facing Components
(PFC) [11]. The needs of controlled and reproducible
plasma start-up and Tritium removal e.g. from the co-
deposited carbon layers, will require applying an
alternative conditioning procedure. ECR Discharge
Conditioning (ECR-DC) and ICRF-DC are fully
compatible with the presence of magnetic fields. ICRF-
DC has already been developed in TEXTOR [12] and in
TORE SUPRA [13] using the present generation of
ICRF antennas, with or without FS. To develop
alternative ITER-relevant scenarios for efficient wall
conditioning in the presence of a high magnetic field,
comparative studies of ICRF-DC / ECR-DC have been
undertaken on TEXTOR using the present ICRH and
ECRH systems without changes in hardware [14,15].
3.1. ECR/ICRF conditioning discharges performance
The results of the experiments clearly show the major
differences in the performance of alternative RF
discharges for the same machine parameters {BT =
(1.65÷2.28) T, pHe≈(3÷6)×10-2 Pa, PICRF≈PECRH≈100
kW÷200 kW}.
ECRH Plasma. High density plasma (n e0
≈2.4×1018 m-3)
is initiated near the resonant layer ce2ωω = (centred at
BT≈1.96 T) and moves outside due to the (E × B)-drift in
a pure toroidal BT. Neutral gas (Helium) breakdown and
ionization occur simultaneously all over the torus
because of microwaves propagating in vacuum. Plasma
production is only possible when the ce2ω layer is
present inside the vessel and with the X-mode
polarization of the microwave beam. ECR discharges are
strongly localized along the path of the microwave
beam, which is focussed in the equatorial plane (Fig10a).
TEXTOR-94: ECR-DC #88214
(a)
ceω=2ω
LFS HFS
TEXTOR-94: ICRF-DC #88217
(b)
ω=5ωcHe+ ω=4ωcHe+=ωcH
LFS HFS
Fig.10. The view of ECR plasma (a) and ICRF
plasma (b) from CCD camera: (BT =2.0 T,
pHe= 3×10-2 Pa, PICRF=90 kW, PECR=150 kW).
ICRF Plasma. ICRF discharge starts from neutral gas
breakdown and initial ionization in the LFS antenna area
(RF waves are not propagating in vacuum). It may
happen when amplitude of the antenna ˜ E z -field in
vacuum satisfies the RF breakdown criterion [9,10]
)(2)()())(( z
2
ez
21
ie eLmrEme ωεω ≤≤ ~
2 . (7)
Here iε is the ionization energy threshold for molecules;
)z(z)(2 zzz dEdEL
~~= is the parallel length scale of the
ponderomotive potential. The RF breakdown time is in
the range tbd ≤ 10 ms at PICRF ≈ 10 kW, pHe≈ 3×10-2 Pa.
Shortly after breakdown (on achieving a threshold
density determined by the condition ωω ≥pe
), the RF
plasma build-up takes place all over the torus during the
remainder of the RF discharge (volume ionization during
the propagating plasma waves phase) and is
characterized by a homogeneous density profile. This is
clearly seen both with a CCD camera (Fig.10b) and with
the 9 channels HCN interferometer. Low-density ICRF
plasmas (n e0
≈0.4×1018 m-3) could easily be produced in
the full range of tested magnetic field BT=1.09 T÷2.30 T,
gas pressure pHe≈ (1÷7)×10-2 Pa and RF power PICRF ≈
30 kW÷120 kW, thus confirming a predicted broad
range of plasma production by the ICRF power [9].
3.2. ECR/ICRF wall conditioning efficiency
To compare quantitatively the conditioning efficiency of
both techniques, the total amount of desorbed molecules
integrated over 1 minute has been measured for each
pulse, taking into account the calibration factor and the
pumping speed for each gas. Figure 11 shows the
evolution of outgassing of H2, HD, H2O, CO and CO2
during a series of 5 ECR-DC and ICRF-DC, performed
in similar conditions. Analysis of such studies revealed a
striking result: the hydrogen removal was about 20 times
higher with ICRF-DC than with ECR-DC and the light
impurities such as H2O, CO and CO2 were not removed
using the ECR discharge produced by a focused
microwave beam [15].
10
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in
H
2
10
m
in
D
C
g
lo
w
in
H
2
ECR-DC ICRF-DC
H 2
H 2
H D
H 2 O
C O
C O 2
Fig.11. Desorption rate of H2, HD, H2O, CO
and CO2 after a series of ECR-DC and ICRF-
DC (BT =2.0 T, pHe =2.5×10-2 Pa, PECR=150
kW, PICRF=60 kW).
However, the combination of ECRH and ICRF power
seems promising for decreasing the RF voltage at the
ICRF antenna and improving the RF power coupling (up
to 36%). Analytical and numerical analysis showed that
ICRF-DC could reasonably be extrapolated to reactor
size fusion devices. As a next step, test of the ICRF
discharge performance in JET with A2 antenna is
planned.
References
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Plasma Phys. and Contr. Fusion,, Montreux 2002, ECA Vol. 26B,
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|
| id | nasplib_isofts_kiev_ua-123456789-80265 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1562-6016 |
| language | English |
| last_indexed | 2025-11-28T17:05:33Z |
| publishDate | 2002 |
| publisher | Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| record_format | dspace |
| spelling | Lyssoivan, A. Messiaen, A. Koch, R. Durodié, F. Amarante-Segundo, G.S. Dumortier, P. Van Eester, D. Vervier, M. Weynants, R. Esser, H.G. Gauthier, E. Hoekzema, F. Philipps, V. Westerhof, E. 2015-04-14T05:48:39Z 2015-04-14T05:48:39Z 2002 New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR / A. Lyssoivan, A. Messiaen, R. Koch, F. Durodié, G.S. Amarante-Segundo, P. Dumortier, D. Van Eester, M. Vervier, R. Weynants, H.G. Esser, E. Gauthier, F. Hoekzema, V. Philipps, E. Westerhof // Вопросы атомной науки и техники. — 2002. — № 4. — С. 24-28. — Бібліогр.: 15 назв. — англ. 1562-6016 https://nasplib.isofts.kiev.ua/handle/123456789/80265 This paper reviews the present status of new developments in ICRF antennas, recent results on more realistic modeling of ICRF antennas using the 3-D full electromagnetic code ICANT and, finally, the latest development in the scenarios of non-traditional applications of HF power for wall conditioning. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Magnetic confinement New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR Article published earlier |
| spellingShingle | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR Lyssoivan, A. Messiaen, A. Koch, R. Durodié, F. Amarante-Segundo, G.S. Dumortier, P. Van Eester, D. Vervier, M. Weynants, R. Esser, H.G. Gauthier, E. Hoekzema, F. Philipps, V. Westerhof, E. Magnetic confinement |
| title | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR |
| title_full | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR |
| title_fullStr | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR |
| title_full_unstemmed | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR |
| title_short | New developments in ICRF antennas and non-traditional applications of HF power on TEXTOR |
| title_sort | new developments in icrf antennas and non-traditional applications of hf power on textor |
| topic | Magnetic confinement |
| topic_facet | Magnetic confinement |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/80265 |
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