Formation of Plasma potential by means of ECH at divertor and peripheral region of plasma

通过 ECH 在偏滤器和等离子体外围区域形成等离子体电势

• 批准号: 08458108
• 负责人: MAEKAWA Takashi
• 金额: $ 4.22万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08458108/
• 关键词: ECH; divertor plasma; plasma potential; LHCD; ダイバータ; ECH; プラズマ周辺電位; 電子バーンスタイン波; 双方向LHCD; 周辺プラズマ; セパラトリックス

Stabilization of plasma has been attained via formation of plasma electric potential or control of pressure profile by means of electron cyclotron heating (ECH). ECH experiments on (1) inner region of plasma, (2) peripheral region and (3) divertor region were planned and done. The results are summarized as follows.(1) In the case of strong magnetic field and/or relatively low electron density, lower hybrid wave (LHW) can propagate into the inner side of plasma, where the tearing instability is suppressed by LH current drive (LHCD) and then a new MIHD instability is destabilized, The experimental results show that this instability is a pressure driven mode and pressure profile control by ECH is quite effective for suppression of the mode.(2) In the case of high electron density, toroidal rotation of plasma is slowed down by LHCD and the tearing mode is mode-locked to the vacuum vessel, and finally plasma disruption takes place. The slowdown of plasma rotation suggests the decrease of plasma potential, which may be ascribed to the loss of LHCD driven fast electrons at the plasma periphery. ECH is quite effective for unlocking of the mode lock and recovery of the plasma toroidal rotation. As a result, the plasma disruption can be avoided. These results suggests that ECH is effective for recovering of potential.(3) Since ECH by using Electron Bernstein waves is assumed to be quite effective for low electron temperature plasma near the divertor region, we have prepared a heating mm wave power source and designed the transmission line and injection antenna for the Bernstein wave heating. In this scheme, trapped electrons in toroidal ripple may be heated and injected into the main plasma via toroidal drift, and plasma potential may be formed at the j3lasma peripheral region.

通过电子回旋加热 (ECH) 形成等离子体电势或控制压力分布，实现了等离子体的稳定。计划并完成了 (1) 等离子体内部区域、(2) 外围区域和 (3) 偏滤器区域的 ECH 实验。结果总结如下：(1)在强磁场和/或相对较低电子密度的情况下，低混合波(LHW)可以传播到等离子体内侧，其中撕裂不稳定性被LH电流驱动抑制(LHCD)，然后出现一种新的MIHD不稳定性，实验结果表明，这种不稳定性是一种压力驱动模式，ECH的压力分布控制对该模式的抑制非常有效。(2)在高电子密度的情况下，等离子体的环形旋转被 LHCD 减慢，撕裂模式被锁模到真空容器，最后发生等离子体破坏。等离子体旋转的减慢表明等离子体电势的降低，这可能归因于等离子体外围 LHCD 驱动的快速电子的损失。 ECH对于解锁模式锁和恢复等离子体环形旋转非常有效。结果，可以避免等离子体破坏。这些结果表明ECH对于电势恢复是有效的。(3)由于使用电子伯恩斯坦波的ECH被认为对于偏滤器区域附近的低电子温度等离子体非常有效，因此我们准备了加热毫米波电源并设计了用于伯恩斯坦波加热的传输线和注入天线。在该方案中，环形波纹中捕获的电子可以被加热并通过环形漂移注入到主等离子体中，并且可以在j3lasma外围区域形成等离子体电势。

项目成果

T.Maekawa: "Evolution of the tearing mode during LHCD induced mode locking in WT-3" Proc.of 16th Int.Conf.on Fusion Energy. Vol.3. 771-775 (1997)

T.Maekawa：“WT-3 中 LHCD 诱导锁模过程中撕裂模式的演化”第 16 届聚变能国际会议论文集。

T.Maekawa: "Evolution of the tearing mode during LHCD-induced mode locking in WT-3" Proc.16th Intern.Conf.on Plasma Phys.and Contr. Nucl.Fusion Research. (発表予定).

T. Maekawa：“WT-3 中 LHCD 诱导模式锁定过程中撕裂模式的演变”Proc.16th Intern.Conf.on Plasma Phys.and Contr.Fusion Research（待提交）。

T.Maekawa: "Control of MHD instability by LHCD and ECH on WT-3" Proc.IAEA TCM on Res.Using Small Fusion Device. 印刷中.

T. Maekawa：“WT-3 上的 LHCD 和 ECH 对 MHD 不稳定性的控制”Proc.IAEA TCM on Res.Using Small Fusion Device 正在出版。

T.Maehara: "Electron Cyclotron Current Drive In A Lower Hybrid Current Drive Plasma" Nuclear Fusion. Vol.38. 39-57 (1998)

T.Maehara：“较低混合电流驱动等离子体中的电子回旋电流驱动”核聚变。

T.Maekawa: "Evolution of the tearing mode during LHCD induced mode locking in WT-3" Proc.of 16th Int.Conf.on Fusion Energy. 3. 771-775 (1997)

T.Maekawa：“WT-3 中 LHCD 诱导锁模过程中撕裂模式的演化”第 16 届聚变能国际会议论文集。