Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison
Over the past decade new regimes of tokamak operation have been identified, whereby electrostatic and magnetic turbulence
 responsible for anomalous transport, can be externally suppressed, leading to improved confinement. Although turbulence
 measurements have been performed on many...
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| Опубліковано в: : | Вопросы атомной науки и техники |
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| Дата: | 2009 |
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2009
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| Цитувати: | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison / G. Van Oost, V. Bulanin, A.J.H. Donné, E. Gusakov, A. Krämer-Flecken, L. Krupnik, J. Heikkinen, A. Melnikov, K. Razumova, V. Rozhansky, J. Stöcke, M. Tendler, M. Van Schoor, V. Vershkov, J. Zajac, A. Altukov, V. Andreev, L. Askinazi, I. Bondarenko, A. Dnestrovskij, L. Eliseev, L. Esipov, S. Grashin, A. Gurchenko, G.M.D. Hogeweij, M. Kantor, E. Kaveeva, T. Kiviniemi, S. Khrebtov, D. Kouprienko, T. Kurki-Suonio, S. Lashkul, S. Lebedev, S. Leerink, S. Lysenko, F. Ogando, S. Perfilov, A. Petrov, A. Popov, D. Shelukhin, R. Shurygin, S. Soldatov, A. Stepanov, Y. Xu // Вопросы атомной науки и техники. — 2009. — № 1. — С. 8-12. — Бібліогр.: 12 назв. — англ. |
Репозитарії
Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1860256946026708992 |
|---|---|
| author | Van Oost, G. Bulanin, V. Donné, A.J.H. Gusakov, E. Krämer-Flecken, A. Krupnik, L. Heikkinen, J. Melnikov, A. Razumova, K. Rozhansky, V. Stöcke, J. Tendler, M. Van Schoor, M. Vershkov, V. Zajac, J. Altukov, A. Andreev, V. Askinazi, L. Bondarenko, I. Dnestrovskij, A. Eliseev, L. Esipov, L. Grashin, S. Gurchenko, A. Hogeweij, G.M.D. Kantor, M. Kaveeva, E. Kiviniemi, T. Khrebtov, S. Kouprienko, D. Kurki-Suonio, T. Lashkul, S. Lebedev, S. Leerink, S. Lysenko, S. Ogando, F. Perfilov, S. Petrov, A. Popov, A. Shelukhin, D. Shurygin, R. Soldatov, S. Stepanov, A. Xu, Y. |
| author_facet | Van Oost, G. Bulanin, V. Donné, A.J.H. Gusakov, E. Krämer-Flecken, A. Krupnik, L. Heikkinen, J. Melnikov, A. Razumova, K. Rozhansky, V. Stöcke, J. Tendler, M. Van Schoor, M. Vershkov, V. Zajac, J. Altukov, A. Andreev, V. Askinazi, L. Bondarenko, I. Dnestrovskij, A. Eliseev, L. Esipov, L. Grashin, S. Gurchenko, A. Hogeweij, G.M.D. Kantor, M. Kaveeva, E. Kiviniemi, T. Khrebtov, S. Kouprienko, D. Kurki-Suonio, T. Lashkul, S. Lebedev, S. Leerink, S. Lysenko, S. Ogando, F. Perfilov, S. Petrov, A. Popov, A. Shelukhin, D. Shurygin, R. Soldatov, S. Stepanov, A. Xu, Y. |
| citation_txt | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison / G. Van Oost, V. Bulanin, A.J.H. Donné, E. Gusakov, A. Krämer-Flecken, L. Krupnik, J. Heikkinen, A. Melnikov, K. Razumova, V. Rozhansky, J. Stöcke, M. Tendler, M. Van Schoor, V. Vershkov, J. Zajac, A. Altukov, V. Andreev, L. Askinazi, I. Bondarenko, A. Dnestrovskij, L. Eliseev, L. Esipov, S. Grashin, A. Gurchenko, G.M.D. Hogeweij, M. Kantor, E. Kaveeva, T. Kiviniemi, S. Khrebtov, D. Kouprienko, T. Kurki-Suonio, S. Lashkul, S. Lebedev, S. Leerink, S. Lysenko, F. Ogando, S. Perfilov, A. Petrov, A. Popov, D. Shelukhin, R. Shurygin, S. Soldatov, A. Stepanov, Y. Xu // Вопросы атомной науки и техники. — 2009. — № 1. — С. 8-12. — Бібліогр.: 12 назв. — англ. |
| collection | DSpace DC |
| container_title | Вопросы атомной науки и техники |
| description | Over the past decade new regimes of tokamak operation have been identified, whereby electrostatic and magnetic turbulence
responsible for anomalous transport, can be externally suppressed, leading to improved confinement. Although turbulence
measurements have been performed on many confinement devices, the insight gained from these experiments is relatively
limited. To make further progress in the understanding of plasma turbulence in relation to improved confinement and transport
barriers, an extensive experimental and theoretical research programme should be undertaken. The present INTAS project
investigates the correlations between on the one hand the occurrence of transport barriers and improved confinement in the
tokamaks TEXTOR & T-10 and Tore Supra as well as on the smaller-scale tokamaks FT-2, TUMAN-3M and CASTOR, and on
the other hand electric fields, modified magnetic shear and electrostatic and magnetic turbulence using advanced diagnostics with
high spatial and temporal resolution. This is done in a strongly coordinated way and exploiting the complementarity of TEXTOR
and T-10 and the backup potential of the other tokamaks, which together have all the relevant experimental tools and theoretical
expertise. Advanced theoretical models and numerical simulations are used to check the experimental results.
За останні десять років було отримано нові режими роботи токамаків, у яких електростатична і магнітна
турбулентність, відповідальна за аномальний перенос, могла заглушатися шляхом зовнішнього впливу, і тим самим
досягалося поліпшене утримання. Незважаючи на те, що дослідження турбулентності проводилися на багатьох установках,
розуміння цих процесів залишається досить обмеженим. Для досягнення подальшого прогресу в розумінні плазмової
турбулентності з погляду поліпшеного утримання і транспортних бар'єрів необхідні інтенсивні експериментальні і
теоретичні дослідження. Проект INTAS спрямовано на з'ясування кореляції між виникненням транспортних бар'єрів і
поліпшеного утримання в токамаках TEXTOR, Т-10 і Tore Supra, а також у токамаках малих розмірів ФТ-2, ТУМАН-3М и
CASTOR, з одного боку, і електричними полями, модифікованим магнітним широм і електростатичною і магнітною
турбулентністю, з іншого боку, з використанням передових діагностичних засобів з високим просторовим і тимчасовим
розділенням. Дослідження проводяться з високим ступенем координації робіт і використанням взаємодоповнюваності
установок TEXTOR і Т-10, і можливостей інших токамаків, що в сукупності забезпечить необхідну експериментальну і
теоретичну перевірку. Для перевірки експериментальних результатів буде використано нові теоретичні моделі і чисельне
моделювання.
В последние десять лет были получены новые режимы работы токамаков, в которых электростатическая и магнитная
турбулентность, ответственная за аномальный перенос, могла подавляться путём внешнего воздействия, и тем самым
достигалось улучшенное удержание. Несмотря на то, что исследования турбулентности проводились на многих установках,
понимание этих процессов остаётся весьма ограниченным. Для достижения дальнейшего прогресса в понимании
плазменной турбулентности с точки зрения улучшенного удержания и транспортных барьеров необходимы интенсивные
экспериментальные и теоретические исследования. Проект INTAS направлен на выяснение корреляции между
возникновением транспортных барьеров и улучшенного удержания в токамаках TEXTOR, Т-10 и Tore Supra, а также в
токамаках малых размеров ФТ-2, ТУМАН-3М и CASTOR, с одной стороны, и электрическими полями, модифицированным
магнитным широм и электростатической и магнитной турбулентностью, с другой стороны, с использованием передовых
диагностических средств с высоким пространственным и временным разрешением. Исследования проводятся с высокой
степенью координации работ и использованием взаимодополняемости установок TEXTOR и Т-10, и возможностей других
токамаков, что в совокупности обеспечит необходимую экспериментальную и теоретическую проверку. Для проверки
экспериментальных результатов будут использованы новые теоретические модели и численное моделирование.
|
| first_indexed | 2025-12-07T18:50:08Z |
| format | Article |
| fulltext |
8 PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2009. № 1.
Series: Plasma Physics (15), p. 8-12.
ROLE OF TURBULENCE AND ELECTRIC FIELDS IN THE FORMATION
OF TRANSPORT BARRIERS AND THE ESTABLISHMENT
OF IMPROVED CONFINEMENT IN TOKAMAK PLASMAS
THROUGH INTER-MACHINE COMPARISON
G. Van Oost 1, V. Bulanin 2, A.J.H. Donné 3, E. Gusakov 4, A. Krämer-Flecken 5, L. Krupnik 6, J. Heikkinen 7,
A. Melnikov 8, K. Razumova 8, V. Rozhansky 2, J. Stöcke 9, M. Tendler 10, M. Van Schoor 11, V. Vershkov 8, J. Zajac 9,
A. Altukov 4, V. Andreev 8, L. Askinazi 4, I. Bondarenko 6, A. Dnestrovskij 8, L. Eliseev 8, L. Esipov 4, S. Grashin 8,
A. Gurchenko 4, G.M.D. Hogeweij 3, M. Kantor 4, E. Kaveeva 2, T. Kiviniemi 7, S. Khrebtov 6, D. Kouprienko 4,
T. Kurki-Suonio7, S. Lashkul 4, S. Lebedev 4, S. Leerink 7, S. Lysenko 8, F. Ogando7, S. Perfilov 8, A. Petrov 2, A. Popov 4,
D. Shelukhin 8, R. Shurygin 8, S. Soldatov 1,5, A. Stepanov 4, Y. Xu 11
1Department of Applied Physics, Ghent University, Ghent, Belgium;
2St-Petersburg State Polytechnical University, St-Petersburg, Russia;
3FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM,
Nieuwegein, The Netherlands;
4Ioffe Institute, St-Petersburg, Russia;
5Institute for Energy Research-Plasma Physics, Forschungszentrum Jülich GmbH,
EURATOM Association, Jülich, Germany;
6Institute of Plasma Physics, NSC “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine;
7Euratom-Tekes Association, VTT, Finland;
8RRC Kurchatov Institute, Moscow, Russia;
9Institute Plasma Physics, Association EURATOM/IPP.CR, Prague, Czech Republic;
10Alfvén Laboratory, Royal Institute of Technology, Stockholm, Sweden;
11Laboratory for Plasma Physics, ERM/KMS, Association EURATOM-Belgian State,Brussels, Belgium
Over the past decade new regimes of tokamak operation have been identified, whereby electrostatic and magnetic turbulence
responsible for anomalous transport, can be externally suppressed, leading to improved confinement. Although turbulence
measurements have been performed on many confinement devices, the insight gained from these experiments is relatively
limited. To make further progress in the understanding of plasma turbulence in relation to improved confinement and transport
barriers, an extensive experimental and theoretical research programme should be undertaken. The present INTAS project
investigates the correlations between on the one hand the occurrence of transport barriers and improved confinement in the
tokamaks TEXTOR & T-10 and Tore Supra as well as on the smaller-scale tokamaks FT-2, TUMAN-3M and CASTOR, and on
the other hand electric fields, modified magnetic shear and electrostatic and magnetic turbulence using advanced diagnostics with
high spatial and temporal resolution. This is done in a strongly coordinated way and exploiting the complementarity of TEXTOR
and T-10 and the backup potential of the other tokamaks, which together have all the relevant experimental tools and theoretical
expertise. Advanced theoretical models and numerical simulations are used to check the experimental results.
PACS 52.55.Fa, 52.30.-q, 52.35Ra, 52.55.-s
1. INTRODUCTION
Local zones (called edge transport barriers ETBs,
respectively internal transport barriers ITBs) with reduced
transport are intensively studied in tokamaks. The
understanding and reduction of turbulent transport in
magnetic confinement devices is not only an academic task,
but also a matter of practical interest, since high confinement
is chosen as the regime for ITER and possible future reactors
because it reduces size and cost.
Generally speaking, turbulence comes in two classes:
electrostatic and magnetic turbulence. Over the last
decade, step by step new regimes of plasma operation
have been identified, whereby turbulence can be
externally controlled, which led to better and better
confinement.The physical picture that is generally given
is that by spinning up the plasma, it is possible to create
flow velocity shear large enough to tear turbulent eddies
apart before they can grow, thus reducing electrostatic
turbulence. This turbulence stabilization concept has the
universality, needed to explain ion transport barriers at
different radii seen in limiter-and divertor tokamaks,
stellarators, reversed field pinches, mirror machines and
linear devices with a variety of discharge- and heating
conditions and edge biasing schemes. The electron heat
conduction, however, which normally is one to two orders
above the collisional lower limit, remained strongly
anomalous also in the regime with suppressed
electrostatic turbulence. In that case it became the
dominant heat loss channel. From this, it is conjectured
that magnetic turbulence drives the anomalous electron
heat conduction.
The investigation of the correlations between on the one
hand the occurrence of transport barriers and improved
confinement in magnetically confined plasmas, and on the
other hand electric fields, modified magnetic shear and
electrostatic and magnetic turbulent fluctuations necessitates
the use of various active means to externally control plasma
transport. It also requires to characterize fluctuations of
various important plasma parameters inside and outside
9
transport barriers and pedestal regions with high spatial and
temporal resolution using advanced diagnostics, and to
elucidate the role of turbulence driving and damping
mechanisms, including the role of the plasma edge
properties. The experimental findings have to be compared
with advanced theoretical models and numerical simulations.
The Consortium of the INTAS project 05-100008-8046
with 14 partner institutions disposes of 6 tokamaks (the
medium-size and similar tokamaks TEXTOR in Jülich and
T-10 in Moscow, the long pulse large French tokamak Tore
Supra in Cadarache, as well as the smaller-scale tokamaks
FT-2, TUMAN-3M in St. Petersburg and CASTOR in
Prague), equipped with advanced diagnostics with high
spatial and temporal resolution. Research activities which are
a continuation and extension of a previous INTAS project [1]
are strongly coordinated and exploit the complementarity of
TEXTOR (mainly ion heating, Dynamic Ergodic Divertor,
DED) and T-10 (electron heating, Heavy Ion Beam Probe,
HIBP) as well as the backup potential of the other tokamaks
which dispose of turbulence diagnostics and/or means of
active control of plasma transport which are complementary
to those of T-10 and TEXTOR, and which provide important
backup information that is very difficult to obtain on larger
tokamaks. Furthermore, strong theoretical and modelling
support is provided.
The most important results obtained in the
investigations of the physical mechanisms underlying
different types of transport barriers are presented in
Section 2. In Section 3 the modeling of plasma dynamics
in ohmically heated FT-2 discharges with the global full f
gyrokinetic particle-in-cell code ELMFIRE is outlined.
2. TRANSPORT BARRIERS: PHYSICAL
MECHANISMS
2.1. ELECTRON INTERNAL TRANSPORT
BARRIERS AND SELF-ORGANIZATION
Recent research in the T-10 and TEXTOR devices has
concentrated on understanding the physical mechanisms
that are responsible for the generation of electron internal
transport barriers (e-ITBs) and also on finding out in
which way they are related to the concept of profile
consistency, in which the plasma pressure and
temperature profiles have a tendency to organize
themselves [2] into an ‘universal’ profile shape, in
agreement with the plasma minimum free energy
principle. If ∇p exceeds a certain critical value,
instabilities connected with the pressure gradient will
counteract the formation of an even steeper gradient. The
radial distribution of transport coefficients is determined
by the necessity to maintain the self-consistent pressure
profile under different external impacts.
From previous experiments on T-10 [3] we know that
ITBs form near the rational surfaces with low numbers m
and n, and that the fluctuation spectrum in this region
does not exhibit the usual peaks and its broadband
component has lower amplitude and shorter correlation
lengths. We tried to investigate the specific effects in
these ITB regions with the help of HIBP diagnostic. We
still did not see any effects on plasma potential and its
fluctuation in the region where we suppose the ITB to
occur. However, the accuracy of determination of the
ITB position at the deepest position available for the
plasma potential analysis was not good enough.
Therefore, further experiments with deeper HIBP
penetration into the plasma core are needed. The
multichannel Thomson scattering diagnostic shows that
the structure of the rational surface (with low n,m) is
very complicated, especially when the ITB is formed
there. Local regions with enhanced Te are registered. For
the investigation of this phenomenon we need more than
one laser pulse per discharge, what we have on
TEXTOR and hope to have on T-10 in the future. To-day
results show that the effect may be asymmetric in
poloidal direction. Further progress in these
investigations may be important to understand the ITB
formation physics.
The tokamak plasma self-organization is a fundamental
turbulent plasma phenomenon, which leads to the
formation of self-consistent pressure profile. This
phenomenon was investigated in T-10 tokamak by means
of different experiments[4, 5]. It was shown that
normalized pressure profile pN(r)=p(r,t)/p(0,t), is
independent on plasma densities in wide range of its
values. Also it was shown that pN(r) is independent on the
auxiliary ECR heating power and its deposition profile.
Experiments show that the pN(r) depends only on the value
of q at the plasma edge, and only weakly on the average
plasma density, and on the deposited power and its radial
distribution. The shape of pN(r) depends on the total plasma
current, but not on j(r) [5]. Special experiments, in
particular with rapid current ramp-up show that the pN(r)
conservation is established during a time tc<0.1τE, with τE
the energy confinement time. As a result of these
experimental investigations it can be concluded that the
self-consistent pressure profile pN(r) in tokamaks is linked
to the equilibrium of a turbulent plasma. Strongly turbulent
plasma can regulate its pressure profile due to its possibility
to change in a wide range transport coefficients changing
the level of instabilities and their coherency. However,
pN(r) exists everywhere, except in the regions where ITBs
occur. In these regions fluctuation coherency decreases,
and more steep pressure gradient are allowed. Tokamaks
with elongated plasma cross section were compared
tokamaks with circular cross section like T-10 using the
model developed by Yu.N. Dnestrovskij. [6] The results
appears to be in a good accordance.
2.2. TRANSPORT BARRIERS INDUCED
BY AN ERGODIC DIVERTOR IN TEXTOR
The influence of a magnetic perturbation field,
generated by the Dynamic Ergodic Divertor (DED), on
the turbulence and transport properties is studied and
compared to plasmas without such a field perturbation.
The external magnetic field breaks up the magnetic field lines
structure and causes an ergodization of the plasma edge [7].
The strength and radial range of the perturbation field can be
widely varied.
One main effect of the DED is the modification of the
radial electric field. The ergodization of the magnetic field
lines leads to an increased electron loss rate which charges the
plasma edge more positively. The application of the DED
increases the rotation in the scrape-off-layer, where the
original rotation is in the ion diamagnetic drift direction. Since
the rotation at radii smaller than the limiter radius is in the
electron diamagnetic drift direction, the DED slows down the
10
rotation. The inversion point of the radial electric field (as well
as the poloidal rotation velocity) is shifted further inside. This
effect does not depend on the DED configuration (m/n= 3/1 or
12/4), but on the field strength of the perturbation field. Note
that this conclusion concerns only DC DED operation; the AC
DED scenarios are the subject of future work.
The data obtained in a single discharge with by the
fast scanning Gundestrup probe (Fig. 1) clearly
demonstrate the effects of DED on the plasma edge
parameters [1].
(a) (b)
(c) (d)
(e) (f )
Fig. 1. Radial profiles (#99777) of the (a) toroidal flow vφ ,
(b) poloidal flow θv , (c) electron temperature eT , (d) electron
density en , (e) floating potential fφ and, (f) radial electric
field rE before (thin line) and during (thick line) DED in
TEXTOR. The vertical dashed line marks the position of the
Last Closed Flux Surface(LCFS). The dashed-dotted line
indicates the end of the reliability of the Gundestrup probe data
The influence of the DED on edge turbulence and
turbulence-induced transport has been investigated in
TEXTOR by Langmuir probes under three different static
DED configurations [8]. Common features are observed.
With DED, the edge equilibrium profiles are altered and
the resultant positive Er is in agreement with modelling.
In the ergodic zone, the potential fluctuations are strongly
reduced and the local turbulent flux changes direction
from radially outwards to inwards. In the same zone, the
turbulence properties are profoundly modified by energy
redistribution in frequency spectra, suppression of large-
scale structures and reduction of the radial and poloidal
correlation lengths for all frequencies. Meanwhile, the
fluctuation poloidal phase velocity changes sign from the
electron to ion diamagnetic drift, consistent with the
change of the Er ×B flow, whereas the slight radially
outward propagation of fluctuations is hindered by the
DED. In the laminar region, the turbulence correlation is
found to react to the observed reduced flow shear.
The radial profiles of electrostatic Reynolds stress and
fluctuation-driven particle flux have been measured in the
plasma boundary using a multi-array of fast reciprocating
Langmuir probes during the static 6/2 and 3/1 mode DED
operation on TEXTOR [9]. In the ohmic discharge phase
before DED, a large radial gradient of Reynolds stress is
observed around the flow shear region, suggesting the
importance of turbulence-driven flows in the plasma edge.
With DED, it is shown that the magnetic ergodization
may suppress the Reynolds stress at the plasma boundary
and thus rearrange the profile of poloidal momentum.
2.3. IMPACT OF MHD ACTIVITY ON EDGE
TRANSPORT BARRIERS IN TUMAN-3M
AND FT-2
The influence of low frequency magnetohydrodynamic
(MHD) activity bursts during ohmic H-mode in the
TUMAN-3M tokamak [10] has been studied focusing on the
measurements of plasma fluctuation poloidal velocity
performed by microwave Doppler reflectometry. During the
MHD burst a transient deterioration of improved confinement
was observed. As shown in Fig. 2 the plasma fluctuation
poloidal rotation observed before the MHD burst in the
vicinity of the edge transport barrier was in the direction of
plasma drift in the negative radial electric field.
1
2
3
4
6
-1
0
1
50 55 60 65 70
16
20
24
L-H
ne, 1013 cm-3
(a)
(b)
D
α
, a
.u
.
(c)
MHD, a.u.
-1
0
1
2
3
4
5
electron diamagnetic drift(d)
time, ms
r c,
cm
ion diamagnetic drift
V θ
, 1
05 cm
/s
VMHD
(e)
Fig 2. Time evolution of the signals measured in a shot virtually
without MHD activity (dotted line) and in a shot with a sharp
MHD in TUMAN-3M:
a) line averaged plasma density measured along central chord;
b) Dα emission intensity; c) magnetic probe signal with MHD
burst; d) magnetic island poloidal velocity derived from magnetic
probe signal evolution (thick grey curve) and the Doppler
velocities; e) cut-off radii (dotted line, microwave frequency
23.5 GHz and solid line, microwave frequency 24.68 GHz)
During the MHD activity the measured poloidal velocity
was drastically decreased and even changed its sign. Radial
profiles of the poloidal velocity measured in a series of
reproducible tokamak shots exhibited the plasma fluctuation
rotation in the ion diamagnetic drift direction at the location of
the peripheral transport barrier. The positive Er perturbation at
the plasma edge obviously leads to a transient deterioration of
the H-mode transport barrier.
According to the HIBP diagnostic the potential in the
central region of TUMAN-3M also changed sign and
became positive during MHD events while normally it is
negative. There exists experimental evidence that MHD
activity is associated with the growth of a magnetic island
at a flux surface in the core a few centimeters inside the
LCFS, as well as the growth of smaller islands at q=4 and
q=2 surfaces, and formation of a stochastic layer in the
LCFS vicinity.
11
A model for the origin of the positive radial electric field
during the rise of the MHD activity is put forward, based on
the assumption of the existence of a strong radial flux of
electrons associated with the formation of an ergodic layer.
The radial electron flux requires the same radial flux of ions
to provide quasi-neutrality. To create the positive radial ion
current the radial electric field should become more positive.
This situation is similar to edge biasing experiments and a
corresponding theory has been already developed before. A
similar model has been used recently to explain the observed
dependence of the radial electric field on the level of
ergodization during experiments with DED on TEXTOR. In
the extreme case, when the electron conductivity associated
with the stochastic layer dominates over the ion conductivity
which occurs in the TUMAN-3M experiments, the radial
electric field should become positive inside the stochastic
layer. The radial ion current generates toroidal rotation in the
co-current direction by the toroidal jxB torque, so the
ergodic layer becomes the source of the toroidal momentum.
The co-current toroidal rotation should be transported
outside the ergodic layer to the core by the turbulent
viscosity thus creating the co-current toroidal rotation in the
center of a tokamak. The co-current toroidal rotation makes
the radial electric field more positive also outside the ergodic
layer and for sufficiently large toroidal rotation the radial
electric field becomes positive also in the central regions in
accordance with the observations.
The influence of the MHD activity on edge transport
barrier has also been studied on the FT-2 tokamak with
enhanced power level of Lower Hybrid Heating
(PLHH ≈ 2POH = 180 kW). Two types of discharge with strong
and weak MHD activity near rational surface q = 4 have been
observed in the post-heating stage. The different MHD
behavior is accompanied by a different character of the plasma
density increase during the RF pulse and different
displacement of the plasma column along the major radius. In
the presence of MHD activity burst, there appears a strong
perturbation of the velocity derived from Doppler frequency
shift. A sharp decrease in the velocity of rotation in the
electron diamagnetic drift direction occurred, and moreover, a
reversal of velocity took place in case of strong MHD activity.
The original mechanism of such velocity evolution may be
fast plasma displacement along the major radius or/and the
MHD development itself. In any case the most plausible
reason for the occurrence of rotation in the ion diamagnetic
drift direction is a dramatic change in the electron–ion balance.
It could be caused by the parallel escape of the fast electrons to
the limiter due to magnetic flux surface distortion or
displacement. The hard X-ray burst might be an indication of
this fast electron loss. The effect is similar to the impact of an
ergodic divertor on plasma rotation.
Close connection between the rotation of the scattering
fluctuations and their level has been observed in the
experiments. Approximately over the whole frequency range
(up to 1MHz) fluctuation suppression is observed slightly before
the velocity inversion occurred due to the cut-off movement
through last closed flux surface. It can be assumed that the
fluctuation suppression is due to strong shear of plasma rotation.
The actual derived velocity with respect to the laboratory
frame is the sum of the fluctuation phase velocity and the
plasma rotation velocity. Therefore, it is useful to compare the
Doppler reflectometry data with those of another measurement.
In the FT-2 tokamak experiment the plasma poloidal velocity
was measured also using Doppler spectroscopy of impurity ion
lines and the velocity was determined from the ion radial force
balance. The radial profiles of the poloidal plasma velocity are
compared with the profiles of the velocity derived from the
Doppler reflectometry measurements [1]. The profiles were
close to each other at the end of the Lower Hybrid Heating pulse
and in the post -heating stage. However, the differences between
the profiles are bigger than the diagnostic uncertainty for the
ohmic heating stage and for the beginning of the RF pulse,
requiring further analysis.
3. GYROKINETIC FULL F PARTICLE
SIMULATION OF FT-2
Plasma dynamics in ohmically heated FT-2 discharges were
modelled with the global full f gyrokinetic particle-in-cell code
ELMFIRE [11,12]. With this code, one has been able for the
first time to model a tokamak discharge with turbulence and
neoclassical dynamics present at the same time. The code can
follow the plasma density, temperature, and various moments of
the distribution function of ions (including oxygen impurity
ions) and electrons together with the electrostatic potential in a
dense spatio-temporal grid in toroidal configuration. The code
can extract the heat and particle losses as well as specify the
power deposition. It can Fourier analyse the mode spectrum in
turbulence and isolate the effect of the slowly varying
neoclassical fields and transport. The code outputs the particle
and heat diffusivities as well as the Reynolds stress.
ELMFIRE was further developed and applied in the study
of dynamics of the radial electric field in the FT-2 tokamak. The
diagnostics of the ELMFIRE code variables and their
correlation analysis were used together with the frequency shift
in the Doppler reflectometric signal at the outer plasma regions
of the FT-2 tokamak plasma in ohmic plasma heating
conditions.
The neoclassical radial electric field and the concomitant
ExB poloidal flow were evaluated. In the plasma code, the field
was found to agree with the neoclassical estimate but at the outer
edge, the field was somewhat clamped, probably due to the
Reynolds stress effects arising from the turbulence. At the outer
edge, the correlation analysis of the turbulence was used
together with a synthetic Doppler reflectometry model to extract
the modelled spectrum of the frequency of the reflected signal.
The shift in the spectrum was interpreted as to arise from the
plasma ExB flow and from the phase velocity (in electron
diamagnetic direction) of the major drift modes responsible for
the microwave reflection in the reflectometry. Agreement of the
reflectometry frequency shift between the experiment and
ELMFIRE prediction for ohmic FT-2 plasma discharge was
found. Moreover, the estimated phase velocity of the modes
from ELMFIRE was found to agree with the corresponding
flux-tube gyrokinetic code GS2 (in ballooning eigenmode
approximation) result for the same wave vector of fluctuations
under same plasma conditions. Agreement between the
ELMFIRE calculated radial electric field and an analytical
neoclassical estimate was found in ohmic core plasmas.
4. CONCLUSIONS AND OUTLOOK
The experimental and theoretical investigation of the
correlations between on the one hand the occurrence of
transport barriers and improved confinement, and on the other
hand electric fields, modified magnetic shear and electrostatic
and magnetic turbulence in tokamaks is of crucial importance,
12
because the ITER project relies mostly on scaling laws. A
thorough understanding can pave new ways towards advanced
scenarios and their external control, and hence lead to an
optimized construction of next generation tokamaks. The
strong innovation potential of this INTAS project using six
tokamaks in the EU (TEXTOR , Tore Supra, COMPASS) and
in Russia (T-10, FT-2 TUMAN-3M), lies in the field of
tokamak physics and tools to control plasma turbulence and
electric fields, as well as in the field of advanced plasma
diagnostics with high spatial and temporal resolution. This
running project has already made a substantial contribution to
an improved understanding of the relation between the global
confinement properties of tokamak plasmas and the physics of
the electrostatic and magnetic turbulence.
ACKNOWLEDGEMENT
The authors are grateful to INTAS (International
Association for the promotion of co-operation with scientists
from the New Independent States of the former Soviet
Union) which supported the research activities in the
framework of project INTAS 1000081-8046.
REFERENCES
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3. K.A. Razumova et al // Nucl. Fusion. 2004, v. 44, p. 1067.
4. K.A. Razumova et al // Plasma Phys. Control. Fusion.
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5. K.A. Razumova et al // Plasma Phys. Control. Fusion 2008,
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6. Yu.N. Dnestrovskij et al // Nucl.Fusion. 2006, v. 46, p. 953.
7. K.H. Finken et al // Fusion Eng.Des. 1997, v. 37, p. 335.
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Article received 12.12.08
РОЛЬ ТУРБУЛЕНТНОСТИ И ЭЛЕКТРИЧЕСКОГО ПОЛЯ В ФОРМИРОВАНИИ ТРАНСПОРТНЫХ
БАРЬЕРОВ И УСТАНОВЛЕНИИ УЛУЧШЕННОГО УДЕРЖАНИЯ В ПЛАЗМЕ ТОКАМАКОВ:
СРАВНЕНИЕ ДАННЫХ ОТ РАЗНЫХ УСТАНОВОК
G. Van Oost, В. Буланин, A.J.H. Donné, Е. Гусаков, A. Krämer-Flecken, Л. Крупник, J. Heikkinen, А. Мельников, К. Разумова,
В. Рожанский, J. Stöckel, M. Tendler, M. Van Schoor, В. Вершков, J. Zajac, А. Алтуков, В. Андреев, Л. Аскинази,
И. Бондаренко, А. Днестровский, Л. Елисеев, Л. Есипов, С. Грашин, А. Гурченко, G.M.D. Hogeweij, М. Кантор, Е. Кавеева,
T. Kiviniemi, С. Хребтов, Д. Куприенко, T. Kurki-Suonio, С. Лашкул, С. Лебедев, S. Leerink, С. Лысенко, F. Ogando,
С. Перфилов, А. Петров, А. Попов, Д. Шелухин, Р. Шурыгин, С. Солдатов, А. Степанов, Y. Xu
В последние десять лет были получены новые режимы работы токамаков, в которых электростатическая и магнитная
турбулентность, ответственная за аномальный перенос, могла подавляться путём внешнего воздействия, и тем самым
достигалось улучшенное удержание. Несмотря на то, что исследования турбулентности проводились на многих установках,
понимание этих процессов остаётся весьма ограниченным. Для достижения дальнейшего прогресса в понимании
плазменной турбулентности с точки зрения улучшенного удержания и транспортных барьеров необходимы интенсивные
экспериментальные и теоретические исследования. Проект INTAS направлен на выяснение корреляции между
возникновением транспортных барьеров и улучшенного удержания в токамаках TEXTOR, Т-10 и Tore Supra, а также в
токамаках малых размеров ФТ-2, ТУМАН-3М и CASTOR, с одной стороны, и электрическими полями, модифицированным
магнитным широм и электростатической и магнитной турбулентностью, с другой стороны, с использованием передовых
диагностических средств с высоким пространственным и временным разрешением. Исследования проводятся с высокой
степенью координации работ и использованием взаимодополняемости установок TEXTOR и Т-10, и возможностей других
токамаков, что в совокупности обеспечит необходимую экспериментальную и теоретическую проверку. Для проверки
экспериментальных результатов будут использованы новые теоретические модели и численное моделирование.
РОЛЬ ТУРБУЛЕНТНОСТІ Й ЕЛЕКТРИЧНОГО ПОЛЯ У ФОРМУВАННІ ТРАНСПОРТНИХ БАР'ЄРІВ
І ВСТАНОВЛЕННІ ПОЛІПШЕНОГО УТРИМАННЯ В ПЛАЗМІ ТОКАМАКІВ:
ПОРІВНЯННЯ ДАНИХ ВІД РІЗНИХ УСТАНОВОК
G. Van Oost, В. Буланін, A.J.H. Donné, Є. Гусаков, A. Krämer-Flecken, Л. Крупнік, J. Heikkinen, О. Мельников, К. Разумова, В. Рожанський,
J. Stöckel, M. Tendler, M. Van Schoor, В. Вершков, J. Zajac, А. Алтуков, В. Андреєв, Л. Аскиназі, І. Бондаренко, А. Днестровський,
Л. Елісеєв, Л. Єсипов, С. Грашин, А. Гурченко, G.M.D. Hogeweij, М. Кантор, Є. Кавеєва, T. Kiviniemi, С. Хребтов, Д. Куприєнко,
T. Kurki-Suonio, С. Лашкул, С. Лебедєв, S. Leerink, С. Лисенко, F. Ogando, С. Перфілов, А. Петров, А. Попов, Д. Шелухін, Р. Шуригін,
С. Солдатов, А. Степанов, Y. Xu
За останні десять років було отримано нові режими роботи токамаків, у яких електростатична і магнітна
турбулентність, відповідальна за аномальний перенос, могла заглушатися шляхом зовнішнього впливу, і тим самим
досягалося поліпшене утримання. Незважаючи на те, що дослідження турбулентності проводилися на багатьох установках,
розуміння цих процесів залишається досить обмеженим. Для досягнення подальшого прогресу в розумінні плазмової
турбулентності з погляду поліпшеного утримання і транспортних бар'єрів необхідні інтенсивні експериментальні і
теоретичні дослідження. Проект INTAS спрямовано на з'ясування кореляції між виникненням транспортних бар'єрів і
поліпшеного утримання в токамаках TEXTOR, Т-10 і Tore Supra, а також у токамаках малих розмірів ФТ-2, ТУМАН-3М и
CASTOR, з одного боку, і електричними полями, модифікованим магнітним широм і електростатичною і магнітною
турбулентністю, з іншого боку, з використанням передових діагностичних засобів з високим просторовим і тимчасовим
розділенням. Дослідження проводяться з високим ступенем координації робіт і використанням взаємодоповнюваності
установок TEXTOR і Т-10, і можливостей інших токамаків, що в сукупності забезпечить необхідну експериментальну і
теоретичну перевірку. Для перевірки експериментальних результатів буде використано нові теоретичні моделі і чисельне
моделювання.
|
| id | nasplib_isofts_kiev_ua-123456789-88129 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1562-6016 |
| language | English |
| last_indexed | 2025-12-07T18:50:08Z |
| publishDate | 2009 |
| publisher | Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| record_format | dspace |
| spelling | Van Oost, G. Bulanin, V. Donné, A.J.H. Gusakov, E. Krämer-Flecken, A. Krupnik, L. Heikkinen, J. Melnikov, A. Razumova, K. Rozhansky, V. Stöcke, J. Tendler, M. Van Schoor, M. Vershkov, V. Zajac, J. Altukov, A. Andreev, V. Askinazi, L. Bondarenko, I. Dnestrovskij, A. Eliseev, L. Esipov, L. Grashin, S. Gurchenko, A. Hogeweij, G.M.D. Kantor, M. Kaveeva, E. Kiviniemi, T. Khrebtov, S. Kouprienko, D. Kurki-Suonio, T. Lashkul, S. Lebedev, S. Leerink, S. Lysenko, S. Ogando, F. Perfilov, S. Petrov, A. Popov, A. Shelukhin, D. Shurygin, R. Soldatov, S. Stepanov, A. Xu, Y. 2015-11-08T16:29:01Z 2015-11-08T16:29:01Z 2009 Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison / G. Van Oost, V. Bulanin, A.J.H. Donné, E. Gusakov, A. Krämer-Flecken, L. Krupnik, J. Heikkinen, A. Melnikov, K. Razumova, V. Rozhansky, J. Stöcke, M. Tendler, M. Van Schoor, V. Vershkov, J. Zajac, A. Altukov, V. Andreev, L. Askinazi, I. Bondarenko, A. Dnestrovskij, L. Eliseev, L. Esipov, S. Grashin, A. Gurchenko, G.M.D. Hogeweij, M. Kantor, E. Kaveeva, T. Kiviniemi, S. Khrebtov, D. Kouprienko, T. Kurki-Suonio, S. Lashkul, S. Lebedev, S. Leerink, S. Lysenko, F. Ogando, S. Perfilov, A. Petrov, A. Popov, D. Shelukhin, R. Shurygin, S. Soldatov, A. Stepanov, Y. Xu // Вопросы атомной науки и техники. — 2009. — № 1. — С. 8-12. — Бібліогр.: 12 назв. — англ. 1562-6016 PACS 52.55.Fa, 52.30.-q, 52.35Ra, 52.55.-s https://nasplib.isofts.kiev.ua/handle/123456789/88129 Over the past decade new regimes of tokamak operation have been identified, whereby electrostatic and magnetic turbulence
 responsible for anomalous transport, can be externally suppressed, leading to improved confinement. Although turbulence
 measurements have been performed on many confinement devices, the insight gained from these experiments is relatively
 limited. To make further progress in the understanding of plasma turbulence in relation to improved confinement and transport
 barriers, an extensive experimental and theoretical research programme should be undertaken. The present INTAS project
 investigates the correlations between on the one hand the occurrence of transport barriers and improved confinement in the
 tokamaks TEXTOR & T-10 and Tore Supra as well as on the smaller-scale tokamaks FT-2, TUMAN-3M and CASTOR, and on
 the other hand electric fields, modified magnetic shear and electrostatic and magnetic turbulence using advanced diagnostics with
 high spatial and temporal resolution. This is done in a strongly coordinated way and exploiting the complementarity of TEXTOR
 and T-10 and the backup potential of the other tokamaks, which together have all the relevant experimental tools and theoretical
 expertise. Advanced theoretical models and numerical simulations are used to check the experimental results. За останні десять років було отримано нові режими роботи токамаків, у яких електростатична і магнітна
 турбулентність, відповідальна за аномальний перенос, могла заглушатися шляхом зовнішнього впливу, і тим самим
 досягалося поліпшене утримання. Незважаючи на те, що дослідження турбулентності проводилися на багатьох установках,
 розуміння цих процесів залишається досить обмеженим. Для досягнення подальшого прогресу в розумінні плазмової
 турбулентності з погляду поліпшеного утримання і транспортних бар'єрів необхідні інтенсивні експериментальні і
 теоретичні дослідження. Проект INTAS спрямовано на з'ясування кореляції між виникненням транспортних бар'єрів і
 поліпшеного утримання в токамаках TEXTOR, Т-10 і Tore Supra, а також у токамаках малих розмірів ФТ-2, ТУМАН-3М и
 CASTOR, з одного боку, і електричними полями, модифікованим магнітним широм і електростатичною і магнітною
 турбулентністю, з іншого боку, з використанням передових діагностичних засобів з високим просторовим і тимчасовим
 розділенням. Дослідження проводяться з високим ступенем координації робіт і використанням взаємодоповнюваності
 установок TEXTOR і Т-10, і можливостей інших токамаків, що в сукупності забезпечить необхідну експериментальну і
 теоретичну перевірку. Для перевірки експериментальних результатів буде використано нові теоретичні моделі і чисельне
 моделювання. В последние десять лет были получены новые режимы работы токамаков, в которых электростатическая и магнитная
 турбулентность, ответственная за аномальный перенос, могла подавляться путём внешнего воздействия, и тем самым
 достигалось улучшенное удержание. Несмотря на то, что исследования турбулентности проводились на многих установках,
 понимание этих процессов остаётся весьма ограниченным. Для достижения дальнейшего прогресса в понимании
 плазменной турбулентности с точки зрения улучшенного удержания и транспортных барьеров необходимы интенсивные
 экспериментальные и теоретические исследования. Проект INTAS направлен на выяснение корреляции между
 возникновением транспортных барьеров и улучшенного удержания в токамаках TEXTOR, Т-10 и Tore Supra, а также в
 токамаках малых размеров ФТ-2, ТУМАН-3М и CASTOR, с одной стороны, и электрическими полями, модифицированным
 магнитным широм и электростатической и магнитной турбулентностью, с другой стороны, с использованием передовых
 диагностических средств с высоким пространственным и временным разрешением. Исследования проводятся с высокой
 степенью координации работ и использованием взаимодополняемости установок TEXTOR и Т-10, и возможностей других
 токамаков, что в совокупности обеспечит необходимую экспериментальную и теоретическую проверку. Для проверки
 экспериментальных результатов будут использованы новые теоретические модели и численное моделирование. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Магнитное удержание Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison Роль турбулентності й електричного поля у формуванні транспортних бар'єрів і встановленні поліпшеного утримання в плазмі токамаків: порівняння даних від різних установок Роль турбулентности и электрического поля в формировании транспортных барьеров и установлении улучшенного удержания в плазме токамаков: сравнение данных от разных установок Article published earlier |
| spellingShingle | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison Van Oost, G. Bulanin, V. Donné, A.J.H. Gusakov, E. Krämer-Flecken, A. Krupnik, L. Heikkinen, J. Melnikov, A. Razumova, K. Rozhansky, V. Stöcke, J. Tendler, M. Van Schoor, M. Vershkov, V. Zajac, J. Altukov, A. Andreev, V. Askinazi, L. Bondarenko, I. Dnestrovskij, A. Eliseev, L. Esipov, L. Grashin, S. Gurchenko, A. Hogeweij, G.M.D. Kantor, M. Kaveeva, E. Kiviniemi, T. Khrebtov, S. Kouprienko, D. Kurki-Suonio, T. Lashkul, S. Lebedev, S. Leerink, S. Lysenko, S. Ogando, F. Perfilov, S. Petrov, A. Popov, A. Shelukhin, D. Shurygin, R. Soldatov, S. Stepanov, A. Xu, Y. Магнитное удержание |
| title | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison |
| title_alt | Роль турбулентності й електричного поля у формуванні транспортних бар'єрів і встановленні поліпшеного утримання в плазмі токамаків: порівняння даних від різних установок Роль турбулентности и электрического поля в формировании транспортных барьеров и установлении улучшенного удержания в плазме токамаков: сравнение данных от разных установок |
| title_full | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison |
| title_fullStr | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison |
| title_full_unstemmed | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison |
| title_short | Role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison |
| title_sort | role of turbulence and electric fields in the formation of transport barriers and the establishment of improved confinement in tokamak plasmas through inter-machine comparison |
| topic | Магнитное удержание |
| topic_facet | Магнитное удержание |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/88129 |
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rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT kramerfleckena rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT krupnikl rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT heikkinenj rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT melnikova rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT razumovak rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT rozhanskyv rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT stockej rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT tendlerm rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT vanschoorm rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT vershkovv rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT zajacj rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT altukova rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT andreevv rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT askinazil rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT bondarenkoi rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT dnestrovskija rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT eliseevl rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT esipovl rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT grashins rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT gurchenkoa rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT hogeweijgmd rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT kantorm rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT kaveevae rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT kiviniemit rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT khrebtovs rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT kouprienkod rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT kurkisuoniot rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT lashkuls rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT lebedevs rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT leerinks rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT lysenkos rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT ogandof rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT perfilovs rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT petrova rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT popova rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT shelukhind rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT shuryginr rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT soldatovs rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT stepanova rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT xuy rolʹturbulentnostíielektričnogopolâuformuvannítransportnihbarêrívívstanovlennípolípšenogoutrimannâvplazmítokamakívporívnânnâdanihvídríznihustanovok AT vanoostg rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT bulaninv rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT donneajh rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT gusakove rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT kramerfleckena rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT krupnikl rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT heikkinenj rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT melnikova rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT razumovak rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT rozhanskyv rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT stockej rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT tendlerm rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT vanschoorm rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT vershkovv rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT zajacj rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT altukova rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT andreevv rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT askinazil rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT bondarenkoi rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT dnestrovskija rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT eliseevl rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT esipovl rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT grashins rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT gurchenkoa rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT hogeweijgmd rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT kantorm rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT kaveevae rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT kiviniemit rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT khrebtovs rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT kouprienkod rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT kurkisuoniot rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT lashkuls rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT lebedevs rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT leerinks rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT lysenkos rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT ogandof rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT perfilovs rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT petrova rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT popova rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT shelukhind rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT shuryginr rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT soldatovs rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT stepanova rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok AT xuy rolʹturbulentnostiiélektričeskogopolâvformirovaniitransportnyhbarʹeroviustanovleniiulučšennogouderžaniâvplazmetokamakovsravneniedannyhotraznyhustanovok |