Abstract
In order to study the magnetic flux exchange at the sawtooth crash, the nonlinear evolution of the tearing mode with poloidal mode number m=1 and toroidal mode number n=1 in the presence of two or three resonant surfaces satisfying q=m/n=1 is examined. It is clarified that whether the local magnetic flux exchange or the internal disruption occurs depends on the initial profile of helical flux function {phi}{sub 0}. Light impurities such as carbon and oxygen and metal impurities such as titanium and molybdenum cause dominant radiation loss in the high density regime and give rise to major disruption. Increasing density by gas puffing while keeping the impurity content constant, the density limit of ohmically heated plasmas is studied. The numerically obtained operational diagram or Hugill diagram, qualitatively agrees well with that obtained in the experiment. Characteristics of global parameter dependence of JT-60 plasmas in both ohmic heating phase and neutral beam heating phase have been studied by using the models of electron and ion thermal diffusivities, {chi}{sub e} and {chi}{sub i}. The predicted T{sub e} profile and the energy confinement time, {tau}{sub E}, show good agreement with experimental data in the medium line for both ohmic heating and neutral beam
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Shirai, Hiroshi
[1]
- Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment
Citation Formats
Shirai, Hiroshi.
Transport studies of tokamak plasmas in JT-60 device.
Japan: N. p.,
1994.
Web.
Shirai, Hiroshi.
Transport studies of tokamak plasmas in JT-60 device.
Japan.
Shirai, Hiroshi.
1994.
"Transport studies of tokamak plasmas in JT-60 device."
Japan.
@misc{etde_10109285,
title = {Transport studies of tokamak plasmas in JT-60 device}
author = {Shirai, Hiroshi}
abstractNote = {In order to study the magnetic flux exchange at the sawtooth crash, the nonlinear evolution of the tearing mode with poloidal mode number m=1 and toroidal mode number n=1 in the presence of two or three resonant surfaces satisfying q=m/n=1 is examined. It is clarified that whether the local magnetic flux exchange or the internal disruption occurs depends on the initial profile of helical flux function {phi}{sub 0}. Light impurities such as carbon and oxygen and metal impurities such as titanium and molybdenum cause dominant radiation loss in the high density regime and give rise to major disruption. Increasing density by gas puffing while keeping the impurity content constant, the density limit of ohmically heated plasmas is studied. The numerically obtained operational diagram or Hugill diagram, qualitatively agrees well with that obtained in the experiment. Characteristics of global parameter dependence of JT-60 plasmas in both ohmic heating phase and neutral beam heating phase have been studied by using the models of electron and ion thermal diffusivities, {chi}{sub e} and {chi}{sub i}. The predicted T{sub e} profile and the energy confinement time, {tau}{sub E}, show good agreement with experimental data in the medium line for both ohmic heating and neutral beam heating phase. The power degradation of energy confinement time ({tau}{sub E}{sup th} {proportional_to}P{sub abs}{sup -1/2}) is also reproduced. Ion temperature profiles of neutral beam heated phase of JT-60 have been simulated by using a {chi}{sub i} model based on {eta}{sub i} mode turbulence and the drift wave turbulence. In case of TFTR L-mode plasmas, the simulated T{sub i} profiles become flatter than experimental data. In the high T{sub i} plasmas of JT-60 and supershot plasmas of TFTR, the predicted T{sub i} profiles become broader compared with the experimental results. (J.P.N.).}
place = {Japan}
year = {1994}
month = {Aug}
}
title = {Transport studies of tokamak plasmas in JT-60 device}
author = {Shirai, Hiroshi}
abstractNote = {In order to study the magnetic flux exchange at the sawtooth crash, the nonlinear evolution of the tearing mode with poloidal mode number m=1 and toroidal mode number n=1 in the presence of two or three resonant surfaces satisfying q=m/n=1 is examined. It is clarified that whether the local magnetic flux exchange or the internal disruption occurs depends on the initial profile of helical flux function {phi}{sub 0}. Light impurities such as carbon and oxygen and metal impurities such as titanium and molybdenum cause dominant radiation loss in the high density regime and give rise to major disruption. Increasing density by gas puffing while keeping the impurity content constant, the density limit of ohmically heated plasmas is studied. The numerically obtained operational diagram or Hugill diagram, qualitatively agrees well with that obtained in the experiment. Characteristics of global parameter dependence of JT-60 plasmas in both ohmic heating phase and neutral beam heating phase have been studied by using the models of electron and ion thermal diffusivities, {chi}{sub e} and {chi}{sub i}. The predicted T{sub e} profile and the energy confinement time, {tau}{sub E}, show good agreement with experimental data in the medium line for both ohmic heating and neutral beam heating phase. The power degradation of energy confinement time ({tau}{sub E}{sup th} {proportional_to}P{sub abs}{sup -1/2}) is also reproduced. Ion temperature profiles of neutral beam heated phase of JT-60 have been simulated by using a {chi}{sub i} model based on {eta}{sub i} mode turbulence and the drift wave turbulence. In case of TFTR L-mode plasmas, the simulated T{sub i} profiles become flatter than experimental data. In the high T{sub i} plasmas of JT-60 and supershot plasmas of TFTR, the predicted T{sub i} profiles become broader compared with the experimental results. (J.P.N.).}
place = {Japan}
year = {1994}
month = {Aug}
}