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Title: Neoclassical transport theory in a tokamak plasma with large spatial gradients

Abstract

Usual neoclassical theories assumed that the spatical inhomogeneity of the plasma was weak. Specifically, this included the following two strong assumptions: banana width was negligible compared to the radial gradient scale length and variation of any physical quantity along the field line was small. This led to the simplification that the spatial inhomogeneity itself did not affect the fundamental transport processes. However, there have been many experimental suggestions that the spatial inhomogeneity may not be small. Firstly, both H-mode and ERS mode experiments have indicated that the finite banana width effect may be important to understand the plasma transport processes. Secondly, the RF and auxiliary heating processes may be sufficiently localized in space so that we may need to consider a strongly inhomogeneous heating effect along the field lines. In the present work we develop a modified neoclassical theory, in parallel with the old theories, which can include the finite banana width effect and the inhomogeneous heating effect. Several new and significant transport terms have been identified, which can play important roles in the understanding of the fundamental transport processes in a tokamak plasma.

Authors:
 [1]
  1. New York Univ., NY (United States)
Publication Date:
OSTI Identifier:
489428
Report Number(s):
CONF-960354-
TRN: 97:011572
Resource Type:
Conference
Resource Relation:
Conference: International Sherwood fusion theory conference, Philadelphia, PA (United States), 18-20 Mar 1996; Other Information: PBD: 1996; Related Information: Is Part Of 1996 international Sherwood fusion theory conference; PB: 244 p.
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; TOKAMAK DEVICES; NEOCLASSICAL TRANSPORT THEORY

Citation Formats

Chang, C.S. Neoclassical transport theory in a tokamak plasma with large spatial gradients. United States: N. p., 1996. Web.
Chang, C.S. Neoclassical transport theory in a tokamak plasma with large spatial gradients. United States.
Chang, C.S. 1996. "Neoclassical transport theory in a tokamak plasma with large spatial gradients". United States. doi:.
@article{osti_489428,
title = {Neoclassical transport theory in a tokamak plasma with large spatial gradients},
author = {Chang, C.S.},
abstractNote = {Usual neoclassical theories assumed that the spatical inhomogeneity of the plasma was weak. Specifically, this included the following two strong assumptions: banana width was negligible compared to the radial gradient scale length and variation of any physical quantity along the field line was small. This led to the simplification that the spatial inhomogeneity itself did not affect the fundamental transport processes. However, there have been many experimental suggestions that the spatial inhomogeneity may not be small. Firstly, both H-mode and ERS mode experiments have indicated that the finite banana width effect may be important to understand the plasma transport processes. Secondly, the RF and auxiliary heating processes may be sufficiently localized in space so that we may need to consider a strongly inhomogeneous heating effect along the field lines. In the present work we develop a modified neoclassical theory, in parallel with the old theories, which can include the finite banana width effect and the inhomogeneous heating effect. Several new and significant transport terms have been identified, which can play important roles in the understanding of the fundamental transport processes in a tokamak plasma.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1996,
month =
}

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