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arXiv 1102.4144physics.plasm-ph
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描述圆柱螺旋放电漂移波的流动等离子体模型

A flowing plasma model to describe drift waves in a cylindrical helicon discharge

L. Chang, M. J. Hole, C. S. Cormac

摘要:

一个双流体模型最初开发描述波振荡的真空电弧离心机,圆柱形,快速旋转,低温和密闭的等离子体柱,适用于解释等离子体振荡的RF产生的线性磁化等离子体(WOMBAT),具有类似的密度和场强。与典型的离心等离子体相比,WOMBAT等离子体具有较慢的归一化旋转频率、较低的温度和较低的轴向速度。尽管存在这些差异,双流体模型提供了一致的描述WOMBAT等离子体配置和产量之间的定性协议测量和预测波振荡频率与轴向场强。此外,该模型预测的密度扰动的径向轮廓与数据是一致的。参数扫描表明,色散曲线对轴向场强和电子温度敏感,振荡频率与电子温度的关系与实验相符。这些结果巩固了早先的说法,密度和浮动电位振荡是一个电阻漂移模式,由密度梯度驱动。据我们所知,这是第一个详细的物理模型的流动等离子体在扩散区远离射频源。可能的扩展模型,包括温度不均匀性和磁场振荡,也进行了讨论。

英文摘要:

A two-fluid model developed originally to describe wave oscillations in the vacuum arc centrifuge, a cylindrical, rapidly rotating, low temperature and confined plasma column, is applied to interpret plasma oscillations in a RF generated linear magnetised plasma (WOMBAT), with similar density and field strength. Compared to typical centrifuge plasmas, WOMBAT plasmas have slower normalised rotation frequency, lower temperature and lower axial velocity. Despite these differences, the two-fluid model provides a consistent description of the WOMBAT plasma configuration and yields qualitative agreement between measured and predicted wave oscillation frequencies with axial field strength. In addition, the radial profile of the density perturbation predicted by this model is consistent with the data. Parameter scans show that the dispersion curve is sensitive to the axial field strength and the electron temperature, and the dependence of oscillation frequency with electron temperature matches the experiment. These results consolidate earlier claims that the density and floating potential oscillations are a resistive drift mode, driven by the density gradient. To our knowledge, this is the first detailed physics model of flowing plasmas in the diffusion region away from the RF source. Possible extensions to the model, including temperature non-uniformity and magnetic field oscillations, are also discussed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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