Studies of structure and dynamics of toroidal plasma using twin heavy ion beam probes

使用双重离子束探针研究环形等离子体的结构和动力学

• 批准号: 15360497
• 负责人: FUJISAWA Akihide
• 金额: $ 7.94万
• 依托单位: National Institute for Fusion Science
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15360497/
• 关键词: zonal flows; turbulence; heavy ion beam probe; electric field; nonlinear coupling; toroidal plasma; bifurcation; CHS; 内部電場; 長距離相関; 乱流輸送; 自励振動; アルベン固有モード; 揺動スペクトル; プラズマ閉じ込め

Since 1982 when H-mode was discovered, a number of structures caused by bifurcation in turbulence transport have been found in toroidal plasma The researchover twenty years has shown that electric field shear can reduce the turbulence and resultant transport to form the local transport barrier and cause the bifurcated structures.Recent simulation and theories expect that the plasma turbulence can generate macroscopic flow through Reynolds stress, and the interaction between macro-scale flow and micro-scale turbulence can affect the saturation level of turbulence and the resultant transport. This is ascribed to the following reasons ; (1)a quasi-energy conservation law is valid for the relation between zonal flow to cause no cross-field transport and turbulence, (2)the time-dependent shear structure of zonal flow also reduces the turbulence. In CHS, using twin heavy ion beam probes constructed with help of this grant-in-aid, the existence of zonal flow was proven in 2004. This is the first achievement in the world. Further more, in 2005 the experiment to prove the nonlinear linkage between zonal flow and turbulence was performed. The experiment successfully verified the existence of such nonlinear interaction between zonal flow and turbulence. In other words, the quasi-energy conservation law was proven using the efficient use of the twin heavy ion beam probes.The phenomena of zonal flow are ubiquitous in nature. The example includes Jovian belt and zones, terrestrial jet stream, solar tacocline and so on. The achievement of this project should give deep insight to the turbulence phenomena widely observed in the universe.

Since 1982 when H-mode was discovered, a number of structures caused by bifurcation in turbulence transport have been found in toroidal plasma The researchover twenty years has shown that electric field shear can reduce the turbulence and resultant transport to form the local transport barrier and cause the bifurcated structures.Recent simulation and theories expect that the plasma turbulence can generate macroscopic flow through Reynolds stress, and the interaction between宏观流量和微尺度的湍流会影响湍流的饱和水平和所得的运输。这归因于以下原因； （1）准能源保护定律对于纬向流量之间的关系有效，不会引起跨场传输和湍流，（2）占时间依赖的纬度流量也会降低湍流。在CHS中，使用借助此赠款构建的双重离子束探针，在2004年证明了区域流的存在。这是世界上的第一个成就。此外，在2005年进行了证明区域流和湍流之间非线性连锁的实验。该实验成功验证了纬向流与湍流之间的这种非线性相互作用的存在。换句话说，使用双重离子束探针有效地使用了准能源保护定律。区域流的现象本质上是无处不在的。该示例包括Jovian带和区域，地面喷射流，太阳Tacocline等。该项目的实现应深入了解宇宙中广泛观察到的湍流现象。

项目成果

Spectrograph of electric field fluctuation in toroidal helical plasma

• DOI: 10.1088/0741-3335/48/4/s03
• 发表时间: 2005-09
• 期刊: Plasma Physics and Controlled Fusion
• 影响因子: 2.2
• 作者: A. Fujisawa;K. Itoh;A. Shimizu;H. Nakano;S. Ohsima;H. Iguchi;K. Matsuoka;S. Okamura;S. Itoh;P. Diamond

Turbulence and transport characteristics of a barrier in a toroidal plasma

• DOI: 10.1088/0741-3335/48/4/s15
• 发表时间: 2006-04-01
• 期刊: PLASMA PHYSICS AND CONTROLLED FUSION
• 影响因子: 2.2
• 作者: Fujisawa, A.;Shimizu, A.;Diamond, P. H.
• 通讯作者: Diamond, P. H.

藤澤 彰英: "Prescription for density profile reconstruction using a heavy ion beam probe"Review of Scientific Instruments. 74. 3335-3340 (2003)

Akihide Fujisawa：“使用重离子束探针重建密度剖面的处方”科学仪器评论 74. 3335-3340 (2003)。

藤澤 彰英: "Experimental studies of structural bifurcation in stellarator plasmas"Plasma Physics and Controlled fusion. 45. R1-R88 (2003)

Akihide Fujisawa：“仿星器等离子体中结构分岔的实验研究”等离子体物理和受控聚变。R1-R88 (2003)。

Internal transport barrier and bifurcation phenomena in stellarators

仿星器中的内部传输势垒和分叉现象

• 发表时间: 2004
• 期刊: Fusion Science and Technology 46
• 作者: A.Fujisawa;K.Itoh;H.Iguchi;K.Matsuoka;et al.(共著);A.Fujisawa
• 通讯作者: A.Fujisawa