Axisymmetric open magnetic systems for plasma confinement
At present, three modern types of different mirror machines for plasma confinement and heating exist in Novosibirsk (Gas Dynamic Trap, -GDT, Multi-mirror, - GOL-3, Tandem Mirror, -AMBAL-M). All these systems are attractive from the engineering point of view because of very simple axisymmetric geomet...
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irk-123456789-802492015-04-15T03:02:07Z Axisymmetric open magnetic systems for plasma confinement Kruglyakov, E.P. Dimov, G.I. Ivanov, A.A. Koidan, V.S. Magnetic confinement At present, three modern types of different mirror machines for plasma confinement and heating exist in Novosibirsk (Gas Dynamic Trap, -GDT, Multi-mirror, - GOL-3, Tandem Mirror, -AMBAL-M). All these systems are attractive from the engineering point of view because of very simple axisymmetric geometry of magnetic configurations. In this paper, the status of different confinement systems is presented. The experiments most crucial for the mirror concept are described such as a demonstration of different principles of suppression of electron heat conductivity (GDT, GOL-3), finding of MHD stable regimes of plasma confinement in axisymmetric geometric of magnetic field (GDT, AMBAL-M), an effective heating of dense plasma by relativistic electron beam (GOL-3), observation of radial diffusion of quiescent plasma with practically classical diffusion coefficient (AMBAL-M), etc. The main plasma parameters achieved in mentioned above systems are presented. 2002 Article Axisymmetric open magnetic systems for plasma confinement / E.P. Kruglyakov, G.I. Dimov, A.A. Ivanov, V.S. Koidan // Вопросы атомной науки и техники. — 2002. — № 4. — С. 29-33. — Бібліогр.: 17 назв. — англ. 1562-6016 PACS: 52.55.Jd http://dspace.nbuv.gov.ua/handle/123456789/80249 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Magnetic confinement Magnetic confinement Kruglyakov, E.P. Dimov, G.I. Ivanov, A.A. Koidan, V.S. Axisymmetric open magnetic systems for plasma confinement Вопросы атомной науки и техники |
| description |
At present, three modern types of different mirror machines for plasma confinement and heating exist in Novosibirsk (Gas Dynamic Trap, -GDT, Multi-mirror, - GOL-3, Tandem Mirror, -AMBAL-M). All these systems are attractive from the engineering point of view because of very simple axisymmetric geometry of magnetic configurations. In this paper, the status of different confinement systems is presented. The experiments most crucial for the mirror concept are described such as a demonstration of different principles of suppression of electron heat conductivity (GDT, GOL-3), finding of MHD stable regimes of plasma confinement in axisymmetric geometric of magnetic field (GDT, AMBAL-M), an effective heating of dense plasma by relativistic electron beam (GOL-3), observation of radial diffusion of quiescent plasma with practically classical diffusion coefficient (AMBAL-M), etc. The main plasma parameters achieved in mentioned above systems are presented. |
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Kruglyakov, E.P. Dimov, G.I. Ivanov, A.A. Koidan, V.S. |
| author_facet |
Kruglyakov, E.P. Dimov, G.I. Ivanov, A.A. Koidan, V.S. |
| author_sort |
Kruglyakov, E.P. |
| title |
Axisymmetric open magnetic systems for plasma confinement |
| title_short |
Axisymmetric open magnetic systems for plasma confinement |
| title_full |
Axisymmetric open magnetic systems for plasma confinement |
| title_fullStr |
Axisymmetric open magnetic systems for plasma confinement |
| title_full_unstemmed |
Axisymmetric open magnetic systems for plasma confinement |
| title_sort |
axisymmetric open magnetic systems for plasma confinement |
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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2002 |
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Magnetic confinement |
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http://dspace.nbuv.gov.ua/handle/123456789/80249 |
| citation_txt |
Axisymmetric open magnetic systems for plasma confinement / E.P. Kruglyakov, G.I. Dimov, A.A. Ivanov, V.S. Koidan // Вопросы атомной науки и техники. — 2002. — № 4. — С. 29-33. — Бібліогр.: 17 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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AT kruglyakovep axisymmetricopenmagneticsystemsforplasmaconfinement AT dimovgi axisymmetricopenmagneticsystemsforplasmaconfinement AT ivanovaa axisymmetricopenmagneticsystemsforplasmaconfinement AT koidanvs axisymmetricopenmagneticsystemsforplasmaconfinement |
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2025-07-06T04:13:03Z |
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2025-07-06T04:13:03Z |
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1836869414650118144 |
| fulltext |
AXISYMMETRIC OPEN MAGNETIC SYSTEMS FOR PLASMA
CONFINEMENT
E.P. Kruglyakov, G.I. Dimov, A.A. Ivanov, V.S. Koidan
Budker Institute of Nuclear Physics, 630090 Novosibirsk, Russia
At present, three modern types of different mirror machines for plasma confinement and heating exist in
Novosibirsk (Gas Dynamic Trap, -GDT, Multi-mirror, - GOL-3, Tandem Mirror, -AMBAL-M). All these systems
are attractive from the engineering point of view because of very simple axisymmetric geometry of magnetic
configurations. In this paper, the status of different confinement systems is presented. The experiments most
crucial for the mirror concept are described such as a demonstration of different principles of suppression of
electron heat conductivity (GDT, GOL-3), finding of MHD stable regimes of plasma confinement in
axisymmetric geometric of magnetic field (GDT, AMBAL-M), an effective heating of dense plasma by
relativistic electron beam (GOL-3), observation of radial diffusion of quiescent plasma with practically
classical diffusion coefficient (AMBAL-M), etc. The main plasma parameters achieved in mentioned above systems
are presented.
PACS: 52.55.Jd
I. INTRODUCTION
At present, there are two main types of magnetic
configurations for plasma confinement: closed (like
tokamak, stellarator, etc) and open (like mirrors).
Advantages of the open systems are as follows.
1.Most of such systems can operate in steady state
regime. At the same time, effects of disruptions are not
appeared in them.
2.Plasma pressure can be comparable with magnetic
field pressure. As to multi-mirror system, the β value, in
this case, can be even significantly higher than unity (so
called “wall confinement”).
3.There are no divertor problems in the mirror case.
4.Open systems are convenient for direct energy
conversion of charged particles. This circumstance can
turn out to be especially important in a future for “low-
neutron” schemes of fusion reactions.
Physical and technological feasibility of controlled
fusion will be finally demonstrated in the frame of ITER
project. However, the program of studies on controlled
fusion will not complete on that. In the nearest future
fusion reactors with D-T fuel seem the most appropriate
from technical point of view. Thus, before the next step of
fusion program (DEMO) after ITER all the structural
materials should be tested on resistance to irradiation by
high power flux of 14 MeV neutrons. It follows from this
that problem of construction of high power neutron
source should be solved as soon as possible. One of the
systems discussed below, namely, gas dynamic trap has a
good perspective as a volumetric neutron source with
rather low tritium and power consumption in comparison
with other candidates. At the same time, the area and
volume of the testing zone in this source are enough for
tests.
At present, studies of plasma confinement and heating
in the open systems are carried out in Japan, Korea and
Russia. The complete set of modern mirror type systems
exists in Novosibirsk. Among them there are multi-mirror
system (GOL-3), gas dynamic trap (GDT), and ambipolar
(tandem) mirror machine (AMBAL-M). The most
important results and the status of Novosibirsk studies in
the field of magnetic mirrors are described in the paper.
II. GAS DYNAMIC TRAP (GDT)
A gas dynamic trap (GDT) for plasma confinement
was first proposed in the Budker Institute [1] as a possible
approach to development of a fusion reactor. It is
essentially one of the simplest systems for magnetic
plasma confinement. As a matter of fact, GDT is an
axially symmetric magnetic mirror of the Budker-Post
type, but with a high mirror ratio (R>10) and with a
mirror to mirror length L exceeding a mean free path λ
for the ion scattering into loss cone. Thus, due to frequent
collisions the plasma confined in the trap is very close to
isotropic Maxwellian state, and, therefore, many
instabilities, which are potentially dangerous for the
classical magnetic mirrors with a collisionless plasma, can
not excite anymore. Moreover, in contrast to the
conventional mirrors, longitudinal plasma losses are not
sensitive to the ion angular scattering rate that might be
enhanced by micro instabilities. This attractive feature of
the GDT plasma confinement can be understood by
consideration of a simple model. Namely, the plasma
losses through the GDT end mirrors qualitatively are
similar to those of a collisional gas in the bottle with a
small hole through which it leaks out. The smaller cross
section of the hole, the longer time is needed for gas to
escape. The total number of particles in the trap is equal
to LSn0 (here n0 is a plasma density and S is the plasma
cross section at the central part of the trap) and the
number of particles leaving the trap through end mirrors
per second can be estimated as n0VTiSm (here VTi is ion
thermal velocity and Sm is the plasma cross section in the
mirrors. Then the confinement time can be determined as
τ ≈ LSn0/Smn0VTi =R⋅L/VTi and it appears to be
proportional to the mirror ratio R and length L of the trap.
According to this relationship, plasma lifetime can be
made long enough and appropriate to the fusion
applications if the device is long enough and mirror ratio
is high. Numerous advantages of the GDT approach
follow from this very simple and reliable physics of
longitudinal plasma confinement and from axial
symmetry of the system. The experiments on study of the
effects of gas dynamic plasma confinement are carried out
on GDT device. The vacuum chamber of the GDT
consists of a cylindrical central cell 7 m long and 1 m in
diameter and two expander tanks attached at both ends.
The device has an axisymmetric magnetic field
configuration. The main parameters of the device are
presented in the Table 1.
Neutral beam injection is used for plasma heating,
Besides, due to oblique injection (at 45° to the axis of the
device) a population of fast sloshing ions is formed. In the
case of injection of tritium and deuterium beams this
population can produce (mostly in the vicinity of turning
points) high power neutron flux.
The experiments on the GDT device have already
enabled to obtain several principal results.
MHD stabilization in Axisymmetric
Geometry
It was successfully demonstrated that the МНD
plasma stability can be achieved in axially symmetric
magnetic field. Flute modes were stabilized by using
external anchor cells in which the field line curvature is
favorable for stability. The stability is achieved if the
contribution of the anchor cells to pressure-weighted
curvature overcomes negative contribution of the central
cell. Remote anchor cells of two different types were
experimentally tested. The first one is an expander end
cell in which the plasma from the mirror throat expands
along gradually decreasing magnetic field to the end
walls. The magnetic field inside the expander end cells is
formed by a combination the above mentioned decreasing
magnetic field of the central cell and the field of
additional large radius expander coils mounted at the end
tanks. A current in these coils is opposite to that of the
Table 1. Parameters of the GDT device.
Parameter Value
Mirror to mirror distance7 mMagnetic field: at midplaneUp to 0.3 TTarget plasma: density3-20×1019m-3Radius at the
midplane8-15 cmElectron temperatureUp to 130 eVNeutral beams: energy15–17 keVpulse duration1.1 msInjection
powerMax 4.1 MWInjection angle45oDensity of fast ions1019m-3Mean energy of fast ions8 –10 keVMaximal
plasma ß40%
2.5-15 T
In mirrors
Fig.1. Plasma potential in the central cell depending on ratio of magnetic field in mirror to the field at the point
where the movable segment of end wall is placed
central cell coils providing the required concave form of
the field lines. An additional coil set installed in one of
the end tank enables to form here a cusp end cell.
Effects of stabilization by the cusp end cell were also
studied. These experiments have shown that the
problem of MHD stabilization of the plasma in the
axisymmetric magnetic configuration can be
successfully solved [3]. Theoretical studies of
ballooning modes stability in GDT predicts that the
central cell β must be less than 0.7-0.8 for stability [4].
In order to obtain such a high β limit, magnetic field
profile in the central cell has to be properly optimized.
For the GDT device, magnetic field in the central cell
differs from this optimized field and, therefore, the β
limit amounts to 0.36 in this case. Recently, on-axis β
exceeding 0.4 was obtained and measured in GDT near
turning point of the fast ions by Motional Stark Effect
diagnostics [5].
Suppression of the Longitudinal Electron
Heat Conduction
One of the most critical issues related to plasma
confinement in mirrors is the danger of too high electron
heat losses due to direct plasma contact to the end wall.
However, for sufficiently high expansion of the field lines
from the mirror to the end wall the theory [6] predicts
strong reduction of the longitudinal electron heat losses.
A nature of this phenomenon links to an increase in
ambipolar potential at the central cell when plasma
density in the flowing out flux decreases significantly
between mirror and end wall. This potential force reflects
back most of the central cell electrons. The ambipolar
potential of the central cell was experimentally measured
as a function of a distance from a movable segment of the
end wall to the mirror [7]. As it is seen in Fig.1, in the
case of large expansion of the magnetic field lines the
movable wall does not influence on plasma potential in
the central cell. Correspondingly, the electron temperature
remains constant. However, when the expansion ratio
decreases (Bm/B(z) < 40 ÷ 50 ~ mM / ), the potential
drops down and the electron temperature in the center cell
falls down thus indicating an increase in longitudinal
losses. It should be pointed out that in the case of plasma
which is heated by relativistic electron beam (GOL-3)
there appeared absolutely another way to suppress the
electron heat flux (see below).
If to estimate perspectives GDT as a fusion reactor,
one should say that from physical point of view such a
reactor will be one of the simplest, because only
axisymmetric coils are used and collisional plasma
behavior is more predictable. However, from technical
viewpoint there are several objections. In [Ref.8] the
parameters of the GDT reactor are presented. To decrease
the length of reactor the use of mirror coils with
Bm = 45 T are supposed. But even in this case, the length
of reactor is estimated to be 3-6 km and the injection
power as 12.3 – 7.5 GW. With a decrease in magnetic
field strength of mirror coils the reactor length and
injection power should be increased. Thus, at present,
there is no realistic decision of the problem of GDT based
reactor. Nevertheless, there exists very important
intermediate step for this concept.
GDT based Neutron Source
Besides fusion reactor, there is another near term
application of the GDT concept. This suggests
construction of a 14 MeV neutron source on the basis of
GDT with a multi-component plasma. The parameters of
such a source (primary neutron flux density is 2 MW/m2,
test zone size is 1m2) are chosen to meet the requirements
of fusion materials testing.
In recent years, several neutron source projects have
been proposed. Among those the GDT based source
seems to be one of the most attractive because of very
moderate consumption of power (60 MW) and tritium
(150 g per year). The main idea of the neutron source
involves an oblique injection of deuterium and tritium
neutral beams with an energy of order of 100 keV into a
’’warm’’ collisional target plasma confined in GDT.
Injection of the neutral beams gives rise to energetic
anisotropic ion population with a density profile being
strongly inhomogeneous along the system axis. The
maximum of the fast ion density will be located in the
vicinities of turning points and the minimum – at the
middle plane of the trap. This results in generation of
strongly inhomogeneous neutron flux with maxima
located at the same place as those of the fast ion density.
Since the neutrons are mostly produced in the fast triton
and deuteron collisions, the neutron specific yield is
proportional to fast ion density squared. Therefore, the
neutron flux peaks near the turning points are even
stronger than those of the density. The effect of neutron
flux peaking was demonstrated in the experiments on the
GDT device with injection of deuterium neutral beams
with energy of 15-17 keV and 4 MW total power incident
at the central cell plasma (see Fig.2). The measured
profile was found to be in reasonable agreement with that
predicted by numerical simulations [2].
The maximum electron temperature that was achieved
so far in the experiments at the GDT device amounts to
130 eV. Taking into account that the neutron flux strongly
increases with the electron temperature, it is now planned
to upgrade the device in order to increase Te up to
250-300 eV. As calculations show, this can be achieved if
the magnetic field at the central cell of the GDT will be
increased from 0.22 up to 0.35 T and the neutron beam
power from 4 up to 10 MW with extension of the pulse
Fig.2. Neutron flux distribution along the axis of GDT
device. Point z = 0 corresponds to the middle plane.
duration from 1 to 4 - 5 ms. It is also assumed that the
injection energy will be increased from 15 - 17 up to 25
keV. In the case if this temperature increase will be
experimentally demonstrated, the construction of the
GDT based neutron source providing neutron flux density
of 350-450 kW/m2 becomes feasible [9]. The full scale
neutron source will provide 2 MW/m2.
III. MULTI-MIRROR SYSTEM GOL-3
From physical point of view the simplest confinement
system could be presented as a pipe with a dense (λi << L)
plasma in the longitudinal magnetic field. (Here L is the
pipe length, λi is the ion mean free path). The time of life
of such the system can be estimated as τ0 ≅ L / VTi,
where VTi is the ion thermal velocity. The size of the
confinement system is large enough, however, if a
corrugated magnetic field with the size of corrugation l
(or what would be the same, single mirror size, l) is used
under condition when l << λi << L, then the longitudinal
expansion of plasma in such a system will have
diffusional character, i.e. τ ≈ L2 / λiVTi. More strictly (see
[Ref.10]), the lifetime is evaluated as τ ≅ R2 L2 / λiVTi = τ
0R2L/ λi (here R is the mirror ratio). It follows from the
formula, that for a dense (more than 1023 m-3) plasma the
length of such fusion reactor could be less than 100
meters. The theory validity [10] was confirmed by special
experiments on alkaline plasma behavior in the multi-
mirror magnetic field [11]. Besides longitudinal
confinement, there is a problem of transverse
confinement. As calculations have shown, in the case of a
dense high temperature plasma, its transverse
confinement will require magnetic field of a few
megagauss. This difficulty can be overcome if to combine
the longitudinal multi-mirror confinement with the
transverse «wall» confinement [12]. In this case, plasma
is placed into a well conducting pipe with relatively
«weak» (~10 T) magnetic field. As calculations have
shown, after fast plasma heating the redistribution of the
magnetic field and plasma density over the pipe cross
section is occurred (see Fig. 3).
The field strength and plasma density at the axis are
not substantially varied. But near the wall they are several
tens times higher (because of two effects: magnetic flux
conservation, and the β value much higher than unity). As
a result, the cooling time of plasma of about 10 cm in
diameter because of strong suppression of the transverse
heat conduction turns to be satisfactory from the
viewpoint of the Lawson criterion at rather moderate
magnetic fields (~10 T) [12]. For experimental checking
of these calculations it is required to put into a plasma a
few hundred kilojoules in a short time. At present, the
most powerful facility GOL-3 for studying the
phenomena of interaction of relativistic electron beam
(REB) with a dense plasma and also for plasma
confinement is under operation in Novosibirsk. The
parameters of GOL-3 are close to those required.
Therefore, the “wall” confinement experiment looks now
quite realistic.
GOL-3 facility can be operated in two modifications
of magnetic field: homogeneous (long solenoid and two
end - mirror coils) for a study of plasma heating by REB,
and multi-mirror modification for the experiments on hot
plasma confinement. Layout of the installation is shown
in Fig.4. Preliminary plasma in GOL-3 is produced in a
stainless steel chamber with 10 cm inner diameter. Plasma
has 8 cm diameter and 12 m in length. Plasma density is
varied within 1020 – 1023m-3 range. Its heating is provided
by powerful REB with energy content of 200 kJ and with
the following parameters: Eb ≈ 1MeV, Ib ≈ 30kA, Ib ≈
8⋅10-6 s. The diameter of the beam in the plasma is 6 cm.
To make an experiment on “wall” confinement in multi-
mirror magnetic field one should solve several problems.
1. Plasma heating with a high efficiency.
2. Suppression of electron heat conduction.
3. Production of hot high β plasma in strong magnetic
field.
One can say that, at present, the two first problems
mainly have been solved.
Plasma Heating by REB
Most of the experiments on study of collective REB-
plasma interaction were made for the case where the
plasma density was 1–2⋅1021 m-3. As a result, rather high
efficiency of the interaction was achieved. In plasma at ne
≈ 1021 m-3 the beam losses up to 40% of its energy were
observed [13]. In these experiments rather high electron
temperature (Te ≈ 2 keV) was obtained. It is important to
note, that so high temperature cannot be reached in the
case of classical electron heat conduction. Fortunately,
because of excitation of microturbulence in plasma due to
REB-plasma interaction an effective electron collision
frequency grows by three orders of magnitude. This effect
leads to significant suppression of longitudinal heat
conduction [14].
As a first step in direction of “wall” confinement
experiments a method of two-stage heating of a dense
plasma has been developed [15]. In this case, preliminary
“rare” (ne ≈ 1021 m-3) plasma is produced with an
additional dense (1022 ÷ 1023 m-3) local bunch. After
heating a “rare” plasma, hot electrons transfer their
energy to electrons and ions of the dense bunch via
classical binary collisions. The experiments show that
peak of pressure is then formed in the range of the bunch.
T, a.u. B
T
B
n
n/n0
n/n0
0.2 0.4 0.6 0.8 1.0
1
2
3
4
0.95 0.97 0.99
40
30
20
10
0.5
1.5
a/a0
Fig.3 Distribution of magnetic field strength B,
plasma density n, and temperature T along
the radius of well conducting pipe after
pulsed plasma heating.
Experiments With Multi-Mirror Confinement
The first experiments on plasma confinement in multi-
mirror geometry were performed in the following way.
Ten mirror cells of 22 cm in length each were formed in
the input and in the output of the facility. About 8 meters
in the central part of the magnetic system were retained
without changes. Mirror ratio in the cells of the
corrugated parts is approximately equal to Bmax/Bmin ≈
1.5. The magnetic field distribution is given in Fig.4.
(Recently the multi-mirror configuration was changed as
it is seen in the figure).
The main result of the recent GOL-3 experiments
consists in the substantial increase in the energy
confinement time. Fig.5. shows the plasma pressure in the
midplane of the solenoid for two confinement systems.
The signal of large amplitude and low duration presents
the shot with plasma heating in 12 m long homogeneous
magnetic field (ne = 2 ⋅1021 m-3). Another one is obtained
for the multi-mirror geometry (ne = 1021 m-3; energy
content of the beam was lowered). New experiments in
this direction are in progress. But even the obtained
results allow to look forward with some optimism.
IV AMBIPOLAR TRAP AMBAL-M
In spite of the fact that the principle of ambipolar
confinement of plasma was proposed in Novosibirsk [16]
quite long ago, up to now, neither the construction of the
ambipolar trap AMBAL with an average min B, nor the
construction of the axisymmetric trap AMBAL-M have
not been completed.
At present, fully axisymmetic system comprises end
mirror with semicusp and part of a long central solenoid
is under operation. The layout of installation and
magnetic field configuration are shown in Fig.6.
Even on this installation the results important for
tandem mirrors have been already obtained:
1. MHD stable hot plasma (Te ≈ 60 eV, Ti ≈ 200 eV, ne
≈ 2 ⋅ 1019 m-3) with length 6 m and with diameter 0.4
m was obtained;
2. A method of plasma production was proposed on the
basis of a use of an annular gas-discharge plasma
source. It was shown that as the result of injection of
annular plasma stream through the input mirror at
solenoid the Kelvin – Helmholtz instability is
excited. This phenomenon led to the stochastic ion
heating. Besides, excitation of electrostatic
oscillations in the plasma led to a significant radial
diffusion and plasma density build-up on the axis;
3. Measurements have shown that during filling the
solenoid by plasma a strong radial diffusion was
observed (D⊥ ≈ 106 cm2/s). After switching of the
plasma source the radial diffusion has fallen down
practically till the classical level (D⊥ ≈ 103 cm2/s);
4. Recently the plasma density up to 6 ⋅ 1019 m-3 was
obtained [17]. This result makes it possible to begin
the experiments on ICRH with the aid of fast
magneto-sound wave.
V. CONCLUSIONS
A number of crucial difficulties intrinsic to open
systems such as large longitudinal electron heat
conduction, problem of MHD stability in axisymmetric
geometry have been solved in recent years. Now the
axisymmetric mirrors, most attractive from engineering
point of view, will be able to provide a plasma with
higher parameters. At present, however, the plasma
parameters in mirrors are far from these in tokamaks.
Therefore, for the nearest years, the main problem
consists in an increase of the plasma parameters.
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sheet beam diode
U-2 generator
of the electron
beam
corrugated magnetic field
solenoid
exit unit
-4 -2 0 2 4 6 8 10 12 14
distance from center of the input mirror, m
0
2
4
6
8
10
B,
T
02
P
O
03
4E
Fig.4. GOL-3 layout and magnetic field distribution
along the axis (the case of multi-mirror geometry).
0 20 40 60 80 100
time, microseconds
0
0.25
0.5
0.75
n(
T e
+T
i),
1
0
ke
v
/m
3
01
PO
03
5F
21
Fig.5 Temporal plasma pressure behavior after heating
by REB for the cases of two magnetic configurations
(homogeneous with two end mirrors and multi-mirror)
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CHEBOTAEV P.Z., 6th Intern Conf. on Plasma Physics and
Controlled Fusion, v.3, p. 535, IAEA, Vienna, (1977).
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CHEBOTAEV P.Z., Journal of Applied Mechanics and
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A.V., et al, Fusion Technology Trans., v. 39, № 1T, p.17 (2001)
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Plasma Confinement (OS-2002), Jeju, Korea, July 1-4, (2002)
T
Fig.6 The layout of AMBAL-M and magnetic field profile along the axis. 1- solenoid, 2- gas discharged plasma
source, 3,4-input and output mirrors of solenoid, 5-end mirror, 6-semicusp.
I.INTRODUCTION
MHD stabilization in Axisymmetric Geometry
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