Up-gradient transport in a probabilistic transport model
- Association EURATOM-Risoe National Laboratory, Optics and Plasma Research, OPL-128 Risoe, DK-4000 Roskilde (Denmark)
The transport of particles or heat against the driving gradient is studied by employing a probabilistic transport model with a characteristic particle step length that depends on the local concentration or heat gradient. When this gradient is larger than a prescribed critical value, the standard deviation of the step size is large compared to its value when the gradient is below critical. For symmetric as well as asymmetric off-axis fueling, the model is capable of producing profiles peaking at the axis. Additionally, profile consistency is obtained over a broad range of source strengths. These results supplement recent works by van Milligen et al. [Phys. Plasmas 11, 3787 (2004)], which applied Levy distributed step sizes in the case of supercritical gradients to obtain the up-gradient transport.
- OSTI ID:
- 20764488
- Journal Information:
- Physics of Plasmas, Vol. 12, Issue 8; Other Information: DOI: 10.1063/1.2001403; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
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