Ergodic mixing for turbulent drift motion in an inhomogeneous magnetic field
- Fusion Research Center, University of Texas, Austin, Texas 78712 (United States)
- Institute for Fusion Studies, University of Texas, Austin, Texas 78712 (United States)
The turbulent {bold E}{times}{bold B} drift of a test particle in an inhomogeneous magnetic field is not reducible to a simple diffusion, but rather leads to a biased diffusion producing an inhomogeneous density distribution (pinch effect). The statistical properties of the long-time chaotic two-dimensional drift motion of a charged particle in the magnetic field {ital B}({ital x},{ital y}) and the time-dependent electrostatic potential {phi}({ital x},{ital y},{ital t}) are studied by numerical symplectic integration. For a conditionally periodic potential with two or more incommensurate frequencies, an ergodic behavior is demonstrated in which the probability density of the particle position is proportional to the magnetic field {ital B}. The accuracy of this prediction is found to be independent of the number {ital N}{sub {omega}} of the incommensurate frequencies for {ital N}{sub {omega}}{ge}2. The relation of this result with the Kolmogorov-Arnold-Moser theory is discussed. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.
- Research Organization:
- University of Texas
- DOE Contract Number:
- FG05-80ET53088
- OSTI ID:
- 124934
- Journal Information:
- Physics of Plasmas, Vol. 2, Issue 10; Other Information: PBD: Oct 1995
- Country of Publication:
- United States
- Language:
- English
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