Improvement of plasma energy confinement in tokamak under radiative cooling of the edge plasma

Razumova, K. A.; Borschegovskiy, A. A.; Gorbunov, E.P.; Dremin, M. M.; Kasyanova, N. V.; Kirneva, N.; Kislov, A. Ya.; Klyuchnikov, L. A.; Krupin, V.A.; Krylov, S.V.; Лысенко, С. Е.; Melnikov, A. V.; Myalton, T.B.; Nemets, A. R.; Notkin, G.E.; Nurgaliev, M. R.; Sarychev, D. V.; Sushkov, A. V.; Chistyakov, V. V.; Ongena, J.; Messiaen, A.

doi:10.1134/s1063780x1711006x

Cited by 8 publications

(18 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is important to check that this is valid also for He, which has Z = 2 and radiates at the very edge of the plasma. In T-10 experiments [12], it was shown that W d saturated at the same level for Ne and He injection for other similar conditions. Plasma in this tokamak was bounded with a circular metal limiter.…”

Section: Dependence Of Energy Confinement On Radiation Lossesmentioning

confidence: 81%

“…To understand this phenomenon, special experiments were performed in the T-10 tokamak (major radius of toroidal plasma R = 1.5 m, minor radius a = 0.3 m), where, in addition to ohmic heating (OH), plasma was heated by ECR power [12]. It has been shown that in conditions where the plasma density is maintained constant by a feedback system (Figure 4), the stored energy W d is independent of the plasma density ( Figure 4a); W d may be increased by 40% due to the Ne injection with a constant density (within 10%).…”

Section: Most Unclear Experimental Fact: Ri Modementioning

confidence: 99%

“…Results of electron cyclotron resonance heating (ECRH) and ohmic heating (OH) experiments with different amounts of injected neon: (a) steady-state values of the stored energy W d vs average plasma density; (b) W d vs radiative loss power P rad . Some points are marked with symbols in order to track them in both figures[12] Reproduced with permission Pleiades Publishing.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Explanation of Experimentally Observed Phenomena in Hot Tokamak Plasmas from the Nonequilibrium Thermodynamics Position

Razumova

Андреев

Kasyanova

et al. 2019

Entropy

View full text Add to dashboard Cite

In studying the hot plasma behavior in tokamak devices, the classical approach for collisional processes is traditionally used. This approach leaves unexplained a number of phenomena observed in experiments related to plasma energy confinement. Further, it is well known that tokamak plasma is always turbulent and self-organized. In the present paper, we show that the nonequilibrium thermodynamics approach allows us to explain many observed dependences and paradoxes; for example, puffing of impurities results in confinement improvement if zones of plasma cooling by impurities and additional plasma heating are not overlapped. The analysis of the experimental results shows the important role of radiation losses at the plasma edge in the processes determining its total energy confinement. It is shown that the generally accepted dependence of energy confinement on plasma density is not quite adequate because it is a consequence of dependence on radiation losses. The phenomenon of the appearance of internal transport barriers and magnetic islands can also be explained by plasma self-organization. The obtained results may be taken into account when calculating the operation of a future tokamak reactor.

show abstract

Section: Dependence Of Energy Confinement On Radiation Lossesmentioning

confidence: 81%

Section: Most Unclear Experimental Fact: Ri Modementioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Explanation of Experimentally Observed Phenomena in Hot Tokamak Plasmas from the Nonequilibrium Thermodynamics Position

Razumova

Андреев

Kasyanova

et al. 2019

Entropy

View full text Add to dashboard Cite

show abstract

“…For this latter purpose, massive neon or argon gas is puffed. The contamination with light impurities can also increase plasma confinement in suitable plasma scenarios [5][6][7][8][9]. It is carried out by injecting a small percentage of impurity gas amount in respect of fuel, in this way the reduction of heat loads on the material plates is realized, meanwhile, a radiative improved confinement can be obtained.…”

Section: Introductionmentioning

confidence: 99%

“…ITER must be investigated in order to extend the knowledge of the impurity mechanism [12,13]. The possibility of exploiting the properties of plasmas contaminated by medium and light Z impurities has being explored in several tokamak devices [5][6][7][8][9], neon, argon and nitrogen are routinely used. JET [14], ASDEX-Upgrade [15] and DIII-D [16] have published detachment studies in helium plasmas.…”

Section: Introductionmentioning

confidence: 99%

Helium injection plasmas in FTU

Mazzotta

Pucella²,

Giovannozzi

et al. 2022

Nucl. Fusion

View full text Add to dashboard Cite

In order to extend observations on the increase of electron density peaking in neon doped plasmas, already reported in FTU Mazzotta et al (2015 Nucl. Fusion 55 073027), some sessions have been performed by injecting helium gas on the L-mode plasmas during the last two experimental campaigns. This favorable scenario, which can fall within so called ‘highly radiative’ or ‘plasma detachment’ themes, is investigated in this paper. The description of the impact of the helium injection on plasma behavior, by varying plasma parameters and shape, is exposed, especially with respect to the density peaking and edge conditioning. It has been recorded that, not only the total amount of puffed helium, but also the injection rate intervenes in triggering a particle inflow. Finally, by using VUV spectroscopy measurements, a model to estimate concentrations of impurities is outlined here for the first time, in this way the helium amount is deduced.

show abstract

Energy Confinement Dynamics and Some Properties of Plasma Self-Organization in ECRH Regime in the L-2M Stellarator

Meshcheryakov

Grishina

2023

Fusion Science and Technology

View full text Add to dashboard Cite

Improvement of plasma energy confinement in tokamak under radiative cooling of the edge plasma

Cited by 8 publications

References 20 publications

Explanation of Experimentally Observed Phenomena in Hot Tokamak Plasmas from the Nonequilibrium Thermodynamics Position

Explanation of Experimentally Observed Phenomena in Hot Tokamak Plasmas from the Nonequilibrium Thermodynamics Position

Helium injection plasmas in FTU

Energy Confinement Dynamics and Some Properties of Plasma Self-Organization in ECRH Regime in the L-2M Stellarator

Contact Info

Product

Resources

About