Effects of orbit squeezing on transport fluxes
Effects of orbit squeezing on transport fluxes
复制标题
轨道压缩对传输通量的影响
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
M. Zarnstorff
中科院分区：
文献类型：
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作者：
K. Shaing;M. Zarnstorff
当μ1i/μ1e的比值为1数量级时，离子轨道挤压会影响电子输运通量，如自举电流。其中，μ1e为电子粘性系数，μ1i为离子粘性系数，其中考虑了离子轨道挤压效应。当离子温度大于电子温度，轨道压缩因子S > 1时，等离子体可以满足μ1i/μ1e ~ 1的条件。计算了大长径比托卡马克的标准挤压香蕉轨道和靠近磁轴的挤压轨道的输运通量。发现在类内质网等离子体中，离子热流和自引导电流都减小了。此外，由于捕获粒子的分数有限，在小半径r的抛物线压力剖面上，自举电流密度不会在磁轴上消失。这使得在稳定状态下操作托卡马克成为可能。
When the ratio μ1i/μ1e is of the order of unity, electron transport fluxes such as bootstrap current can be affected by the ion orbit squeezing. Here, μ1e is the electron viscous coefficient, and μ1i is the ion viscous coefficient with the effects of ion orbit squeezing included. The condition μ1i/μ1e∼1 can be satisfied for plasmas, such as those in enhanced reversed shear (ERS) mode, with ion temperature greater than electron temperature and orbit squeezing factor S≫1. Transport fluxes for both standard squeezed banana orbits and for squeezed orbits close to the magnetic axis are calculated for a large aspect ratio tokamak. It is found that ion heat flux and bootstrap current are reduced in ERS-like plasmas. Furthermore, the bootstrap current density does not vanish on the magnetic axis for a parabolic pressure profile in minor radius r due to the finite value of the fraction of trapped particles. This makes it possible to operate tokamaks in steady state.