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Title: Pulse Propagation in a simple probabilistic transport model

Abstract

The response to perturbations of a simplified transport model is studied. The model is used as a paradigmatic example of transport controlled by a critical gradient. Long-time system behavior is diffusive when most of the system is sub-critical. However, when the critical mechanism becomes significant, it is observed to dominate the system behavior at both short- and long-time scales. While the pulse amplitude decays in an approximately diffusive manner at long times for weakly critical situations, the pulse shape is not self-similar.

Authors:
 [1];  [2];  [2];  [2]
  1. Asociacion EURATOM-CIEMAT
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
931320
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nuclear Fusion; Journal Volume: 47; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; AMPLITUDES; TRANSPORT; PULSES; DISTURBANCES; MATHEMATICAL MODELS; turbulent transport; nondiffusive transport; renormalization theory; fluid closure

Citation Formats

van Milligen, B. Ph., Carreras, Benjamin A, Lynch, Vickie E, and Sanchez, Raul. Pulse Propagation in a simple probabilistic transport model. United States: N. p., 2007. Web. doi:10.1088/0029-5515/47/3/004.
van Milligen, B. Ph., Carreras, Benjamin A, Lynch, Vickie E, & Sanchez, Raul. Pulse Propagation in a simple probabilistic transport model. United States. doi:10.1088/0029-5515/47/3/004.
van Milligen, B. Ph., Carreras, Benjamin A, Lynch, Vickie E, and Sanchez, Raul. Mon . "Pulse Propagation in a simple probabilistic transport model". United States. doi:10.1088/0029-5515/47/3/004.
@article{osti_931320,
title = {Pulse Propagation in a simple probabilistic transport model},
author = {van Milligen, B. Ph. and Carreras, Benjamin A and Lynch, Vickie E and Sanchez, Raul},
abstractNote = {The response to perturbations of a simplified transport model is studied. The model is used as a paradigmatic example of transport controlled by a critical gradient. Long-time system behavior is diffusive when most of the system is sub-critical. However, when the critical mechanism becomes significant, it is observed to dominate the system behavior at both short- and long-time scales. While the pulse amplitude decays in an approximately diffusive manner at long times for weakly critical situations, the pulse shape is not self-similar.},
doi = {10.1088/0029-5515/47/3/004},
journal = {Nuclear Fusion},
number = 3,
volume = 47,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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