Diffusivity Scaling on Shear Flow
Zhong-Tian Wang,
Zhi-Xiong He,
Jia-Qi Dong,
Zhan-Hui Wang,
Shao-Yong Chen,
Chang-Jian Tang
Issue:
Volume 3, Issue 5, September 2014
Pages:
202-206
Received:
4 September 2014
Accepted:
20 September 2014
Published:
30 September 2014
Abstract: Diffusivity scaling on shear flow is investigated. Radial electrical field is the drive of the flow. The turning points of the trapped particle are not on the drift surface, but modified by the radial electrical field. For the first time, an analytical expression of the banana width in presence of shear flow is accurately derived. The particle diffusivity given by Rosenbluth is reproduced but with the shear flow modification.
Abstract: Diffusivity scaling on shear flow is investigated. Radial electrical field is the drive of the flow. The turning points of the trapped particle are not on the drift surface, but modified by the radial electrical field. For the first time, an analytical expression of the banana width in presence of shear flow is accurately derived. The particle diff...
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Quasilinear Theory for Relativistic Particles
Zhong-Tian Wang,
Zhi-Xiong He,
Zhan-Hui Wang,
Min Xu,
Jia-Qi Dong,
Na Wu,
Shao-Yong Chen,
Chang-Jian Tang
Issue:
Volume 3, Issue 5, September 2014
Pages:
207-210
Received:
15 September 2014
Accepted:
25 September 2014
Published:
30 September 2014
Abstract: Quasilinear theory is developed by using canonical variables for relativistic particles. It is self-consistent, including momentum, pitch-angle, and spatial diffusions. By assuming the wave field is a superposition of known toroidal and poloidal Fourier modes, the quasilinear diffusion coefficients are written in a form which can be directly evaluated by using the output of a spectral full-wave solver of Maxwell equations in toroidal plasmas. The formalism is special for tokamaks which are axis-symmetric, therefore, it is simple and suitable for simulations of cyclotron heating, current drive and radio-frequency wave induced radial transport in ITER. PACS: 52.35.Py, 52.50.Sw, 52.35.Fa.
Abstract: Quasilinear theory is developed by using canonical variables for relativistic particles. It is self-consistent, including momentum, pitch-angle, and spatial diffusions. By assuming the wave field is a superposition of known toroidal and poloidal Fourier modes, the quasilinear diffusion coefficients are written in a form which can be directly evalua...
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