Dissertation > Excellent graduate degree dissertation topics show

Study of the MHD Instabilities on SUNIST Spherical Tokamak

Author: WuYanBin
Tutor: ZhongFangChuan
School: Donghua University
Course: Plasma Physics
Keywords: SUNIST MHD instabilities SVD mode analysis
CLC: TL631.24
Type: Master's thesis
Year: 2010
Downloads: 30
Quote: 0
Read: Download Dissertation

Abstract


Spherical tokamak is different from traditional toakamak as its aspect ratio A (A=R/a, R and a are the major and minor radius of device) is closed to 1. In last 20 years, it has attracted a more and more attention and has been widely studied owing to its advantage of compact construction, easily accessed high P, better magnetohydrodynamic (MHD) stabilities. Results of experiments show that MHD instabilities still happen in spherical tokamak, such as vertical displacement event (VDE), sawtooth, kink mode, neoclassical tearing mode (NTM), ELM, internal reconnection events (IRE) and microscope instabilities. It is primary and significant that to study the conditions and mechanism of MHD instabilities, explore the the possible method to avoid or suppress the occurrence of the MHD instabilities and improve the operation parameters of spherical tokamak..SUNIST is the first spherical tokamak build in China. Various MHD instabilities events have been observed on it since the first discharging in 2002, such as Mirov fluctuations and IRE. However, the detail investigation of the instabilities features, such as the mode numbers and the frequency is lacke up to now. The Mirnov fluctuations are measured and analysed by magnetic measurement system on SUNIST Spherical Tokamak. The toroidal and poloidal numbers of Mirnov fluctuations are distinguished by using singular value decomposition (SVD), and the time evolution of the mode numbers during a discharge is presented.The theoretical and experimental research indicated that proper plasma rotation and shear flow will improve MHD instabilities on spherical tokamak. The change of plasma movements is realized by a biased electrode. The electrode produces a electric filed through the radius direction Er, and changes the movements of the grain by ExB drift. As the electric filed can penetrate only a limit length in the high temperature plasma, it is found that the biased electrode has a better result for fluctuations close to plasma boundary.

Related Dissertations

  1. Research on Transfer Alignment of the Missile Onboard the Aircraft,V249.322
  2. Research on Speech Sparse Basis and Projection Matrix Based on Compressed Sensing,TN919.8
  3. Study of Anti-protocol Attacks Digital Image Watermarking Based on SVD,TP309.7
  4. Extraction of Normal Modes Information Using Data-derived Method,P733.2
  5. Research of Distributed Video Codec and Image Super-resolution Based on Compressed Sensing,TP391.41
  6. Research on SAR Images Reducing Speckle Algorithm Based on Sparse Decomposition,TN957.52
  7. The Research on Multi-station Location Method of ULF/ELF Em Radition Source Associated with Seism,P315.7
  8. Vision measurement point cloud data registration method and key technology research,TP391.41
  9. Mode Analysis and Experiment of Airborne Radar Pedestal,TN957.2
  10. Research on Enhanced Prediction and Postprocessing of Video Coding,TN919.81
  11. The Research of the Production, Learning and Research Co-operation Model in Universities Based on the Feedback-based Mode Simulation Analysis,G644
  12. Based on Chaotic Encryption and SVD watermarking algorithm,TP309.7
  13. Digital Watermarking Based on Wavelet,TP309.7
  14. An Image Watermarking Algorithm Based on DWT DCT and SVD,TP309.7
  15. Document Image Watermarking Algorithm Based on Content Authentication,TP391.41
  16. Investigation of Modal Analytical Method on Microwave Transmission Line Discontinuity,TN811
  17. Research on Collaborative Filtering Recommendation Algorithm,TP301.6
  18. LTE uplink channel estimation technology research,TN929.5
  19. Study on the Method of T2 Spectrum Inversion from Nmr Data,P631.8
  20. Airborne engine model and high stability of the adaptive control technology,V233

CLC: > Industrial Technology > Nuclear technology > Controlled thermonuclear reactions ( fusion reaction theory and experimental facilities) > Thermonuclear device > Magnetic confinement devices > Closed plasma device > Tokamak
© 2012 www.DissertationTopic.Net  Mobile