Application of wavelet multiresolution analysis to the study of self-similarity and intermittency of plasma turbulence
Application of wavelet multiresolution analysis to the study of self-similarity and intermittency of plasma turbulence
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DOI：
10.1063/1.2336754
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发表时间：
2006-08
影响因子：
1.6
通讯作者：
G. Xu;B. Wan;W. Zhang
中科院分区：
文献类型：
--
作者：
G. Xu;B. Wan;W. Zhang
小波分析的多分辨率特性使其成为描述湍流信号的有力工具。等离子体湍流类似于其流体湍流对应物，表现出一定程度的自相似性、不连续性和多重分形。采用基于双正交小波的多分辨分析技术对朗缪尔探针数据进行处理，研究了等离子体涨落的自相似性和不稳定性。数据是在HT-7超导托卡马克等离子体边缘区采集的。结果表明，等离子体湍流是由多尺度涡旋组成的，这些涡旋在不同尺度之间具有相似的结构，多尺度涡旋的共存导致了等离子体波动的自相似性。大尺度湍流涡旋间歇性爆发，这些大尺度涡旋与那些小的叠加被发现负责的不稳定行为。小波多分辨率分析在HT-7托卡马克装置上的成功应用表明，它是一种很有前途的技术。
Multiresolution property of wavelet analysis makes it a powerful tool in describing turbulent signals. Plasma turbulence similar to its fluid turbulence counterpart shows a degree of self-similarity, intermittency, and multifractal. The multiresolution analysis technique based on a biorthogonal wavelet was applied to the Langmuir probe data to study the self-similarity and the intermittency of plasma fluctuations. The data were collected in the plasma edge region of the HT-7 superconducting tokamak. It is found that plasma turbulence is composed of multiscale eddies; these eddies are similar in structure between different scales; the coexistence of multiscale eddies results in the self-similarity in plasma fluctuations. Large-scale turbulence eddies intermittently burst out; the superposition of these large-scale eddies with those small ones is found responsible for the intermittency behavior. Success of utilizing wavelet multiresolution analysis in the HT-7 tokamak suggests it is a promising technique in...