Observation of radial propagation of electrostatic fluctuations on KT-C tokamak

Wang, Guiding; Yu, Cong; Liu, Wandong; Yao, Wen; Wan, Shude

doi:10.1088/0741-3335/42/2/305

Cited by 17 publications

(17 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This spectrum differs substantially from that of the AT, which is characterized by a broad peak at nonzero k and zero k r observed in the edge region of several tokamaks. 34,35 The radial spectral structure of the GAM can be seen more clearly in Figs. 3͑b͒ and 3͑c͒, which illustrate the S͑k r , f͒ and S͑k r , f GAM ͒ spectra for Ẽ r fluctuations.…”

Section: B Radial Structure and Propagation Properties Of The Gammentioning

confidence: 93%

Spectral features of the geodesic acoustic mode and its interaction with turbulence in a tokamak plasma

Lan

Liu

et al. 2008

Physics of Plasmas

View full text Add to dashboard Cite

The three-dimensional wavenumber and frequency spectrum for the geodesic acoustic mode (GAM) has been measured in the HuanLiuqi-2A tokamak for the first time. The spectrum provides definite evidence for the GAM, which is characterized by kθ=kϕ=0 and krρi≈0.04−0.09 with the full width at half-maximum Δkrρi≈0.03−0.07. The localized GAM packet is observed to propagate outward in the radial direction with nearly the same phase and group velocity. The envelopes of the radial electric field and density fluctuations are observed to be modulated by the GAM. By comparing the experimental result with that of the envelope analysis using model signals, the mechanism of the envelope modulation has been identified. The results strongly suggest that the envelope modulation of the Ẽr fluctuations is dominantly caused by the direct regulation of the GAM during the GAM generation in the energy-conserving triad interaction, and the envelope modulation of the density fluctuations is induced by the GAM shearing effect, which transfers the fluctuation energy from low to high frequencies. In addition, the cross- and auto-bicoherences for interactions between the GAM and turbulent fluctuations show a similar peaked feature that may reflect the resonant property in the nonlinear coupling between the GAM and turbulent fluctuations.

show abstract

Section: B Radial Structure and Propagation Properties Of The Gammentioning

confidence: 93%

Spectral features of the geodesic acoustic mode and its interaction with turbulence in a tokamak plasma

Lan

Liu

et al. 2008

Physics of Plasmas

View full text Add to dashboard Cite

show abstract

“…Type I ELMy H-modes were obtained in H (1MA/1T, H-NBI) and D (1.7MA/1.7T, D-NBI), with average plasma triangularity δ = 0.3, with matching ρ * , ν * , β and q profiles [3]. Remarkably, it was found that the scaled thermal energy confinement time, Bτ E,th /A, the scaled ELM frequency, A f ELM /B, and the scaled sawtooth frequency, Af saw /B, were all matched within error bars in the H and D plasmas, indicating that the invariance principle was satisfied throughout the entire plasma radius, despite the different physical processes in the plasma centre, core confinement and edge regions [3]. We note that the match in scaled ELM frequency and scaled sawtooth frequency in H and D is not in the original theory of [1] and could have been fortuitous in the experiments reported in [3].…”

Section: Isotope Identity Experiments In Jet-ilw With H and D L-mode mentioning

confidence: 98%

“…Isotope identity experiments exploit the change in isotope ion mass to obtain plasmas with identical dimensionless profiles in the same tokamak. In order to keep ρ * , β, ν * and q profiles fixed when also varying the isotope mass, the plasma current, toroidal magnetic field and the density and temperature must scale, respectively, as: I P , B T ~ A 3/4 ; n ~ A and T ~ √A [3,4]. Accordingly, for equal scaled energy confinement times B τ E,th /A, the absorbed input power must scale as P abs = W th /τ E,th ∼ B 5/3 T (or ~ A 5/4 ), where W th is the thermal stored energy, and the heat diffusivity must scale as χ ~ B/A, with χ defined in terms of the temperature gradient and the heat flux q = −n χ ∇T.…”

Section: Isotope Identity Experiments In Jet-ilw With H and D L-mode mentioning

confidence: 99%

Isotope identity experiments in JET-ILW with H and D L-mode plasmas

et al. 2019

View full text Add to dashboard Cite

NBI-heated L-mode plasmas have been obtained in JET with the Be/W ITER-like wall (JET-ILW) in H and D, with matched profiles of the dimensionless plasma parameters, ρ * , ν * , β and q in the plasma core confinement region and same T i /T e and Z eff . The achieved isotope identity indicates that the confinement scale invariance principle is satisfied in the core confinement region of these plasmas, where the dominant instabilities are Ion Temperature Gradient (ITG) modes. The dimensionless thermal energy confinement time, Ω i τ E,th , and the scaled core plasma heat diffusivity, A χ eff /B T , are identical in H and D within error bars, indicating lack of isotope mass dependence of the dimensionless L-mode thermal energy confinement time in JET-ILW. Predictive flux driven simulations with JETTO-TGLF of the H and D identity pair is in very good agreement with experiment for both isotopes: the stiff core heat transport, typical of JET-ILW NBI heated L-modes, overcomes the local gyro-Bohm scaling of gradient-driven TGLF, explaining the lack of isotope mass dependence in the confinement region of these plasmas. The effect of E × B shearing on the predicted heat and particle transport channels is found to be negligible for these low beta and low momentum input plasmas.

show abstract

“…[1][2][3][4][5][6] Here we only briefly show some results of steady state plasmas under the SMT configuration with or without vertical fields. [1][2][3][4][5][6] Here we only briefly show some results of steady state plasmas under the SMT configuration with or without vertical fields.…”

Section: Results Of the Steady State Operationsmentioning

confidence: 99%

Compatible operation of the power system for steady state and pulse modes in a magnetic torus KT-5D

Wang

et al. 2006

Review of Scientific Instruments

Self Cite

View full text Add to dashboard Cite

Articles you may be interested inDevelopment of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamaka) Rev. Sci. Instrum. 85, 11D838 (2014); 10.1063/1.4887276 Simulations of drift resistive ballooning L-mode turbulence in the edge plasma of the DIII-D tokamaka) Phys. Plasmas 20, 055906 (2013); 10.1063/1.4804638 Optimizing stability, transport, and divertor operation through plasma shaping for steady-state scenario development in DIII-Da) Phys. Plasmas 16, 056116 (2009); 10.1063/1.3125934Monte Carlo operators for ions interacting with radio frequency waves Compatible operation of steady state mode and pulse mode is realized in the KT-5D device. New power supplies with the operation control systems for the steady state toroidal magnetic field as well as for the vertical field are added, and the rf wave injection systems for sustaining steady state plasmas are upgraded. After the modification, the device now can work not only as a tokomak with pulsed plasma currents as it was but also as a simple magnetized torus with steady state plasma discharges. It allows more flexible and efficient experimental researches on the magnetically confined plasmas to be carried on in the same device.

show abstract

Observation of radial propagation of electrostatic fluctuations on KT-C tokamak

Cited by 17 publications

References 16 publications

Spectral features of the geodesic acoustic mode and its interaction with turbulence in a tokamak plasma

Spectral features of the geodesic acoustic mode and its interaction with turbulence in a tokamak plasma

Isotope identity experiments in JET-ILW with H and D L-mode plasmas

Compatible operation of the power system for steady state and pulse modes in a magnetic torus KT-5D

Contact Info

Product

Resources

About