Abstract

In the T-10 tokamak, the results of plasma heating at the first and second electron cyclotron (EC) harmonics differ substantially. However, the problem is multi-parametric, so it is impossible to estimate the heating quality by sight. In this work, the analysis of heating at both harmonics is provided with two transport models, which were constructed separately for simulation in each mode. For the heating on the second harmonic, we solve the inverse problem of determining the profile of the absorbed power from the experimental electron temperature profile. In this mode, we are able to determine both the deposited power profile and the ratio of absorbed to deposited power. It is shown that at low plasma densities, this ratio is small, which, apparently, is a consequence of the low absorption of the heating waves during their single pass though the plasma. During the heating at the second harmonic, the absorbed power profile is much flatter than predicted by ray tracing calculations of EC waves. Multi-pass wave absorption with random reflections from the corrugated chamber wall leads to such absorption profiles. At high plasma densities, the absorbed power is close to the input power. However, in this case, the results at the second harmonic are worse than the results obtained at the first harmonic due to the flatter absorbed density profile.

中文翻译：

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T-10托卡马克中第一和第二电子回旋谐波的等离子体加热比较

摘要

在T-10托卡马克中，在第一和第二电子回旋加速器（EC）谐波处等离子体加热的结果大不相同。然而，问题是多参数的，因此不可能凭视觉估计加热质量。在这项工作中，为两个谐波加热分析提供了两个传输模型，分别构建了每个模型用于仿真。对于二次谐波的加热，我们解决了从实验电子温度曲线确定吸收功率曲线的反问题。在这种模式下，我们能够确定沉积功率分布以及吸收功率与沉积功率之比。结果表明，在低等离子体密度下，该比例很小，显然，这是由于热波单次通过等离子时吸收率低所致。在二次谐波加热期间，吸收的功率曲线比EC波的射线跟踪计算所预测的要平坦得多。来自波纹室壁的随机反射的多次通过波吸收导致这种吸收曲线。在高等离子体密度下，吸收的功率接近输入功率。但是，在这种情况下，由于吸收密度分布曲线较平缓，因此在第二谐波处的结果比在第一谐波处的结果差。来自波纹室壁的随机反射的多次通过波吸收导致这种吸收曲线。在高等离子体密度下，吸收的功率接近输入功率。但是，在这种情况下，由于吸收密度分布曲线较平缓，因此在二次谐波处的结果比在一次谐波处的结果差。来自波纹室壁的随机反射的多次通过波吸收导致这种吸收曲线。在高等离子体密度下，吸收的功率接近输入功率。但是，在这种情况下，由于吸收密度分布曲线较平缓，因此在二次谐波处的结果比在一次谐波处的结果差。