Session 1P - Transport/Numerical Simulations.
POSTER session, Monday morning, November 11
Exhibit Hall - Concourse Level, Adam's Mark
The concept of Self-Organized Criticality (SOC) has been recently advanced as a paradigm for turbulent transport in magnetically confined plasmas [P.H. Diamond and T.S. Hahm, Phys. Plasmas \bf23, 640 (1995); D.E. Newman, B.A. Carreras, P.H. Diamond and T.S. Hahm, Phys. Plasmas, in press]. In SOC systems transport is usually dominated by large events (i.e., avalanches in a sandpile). Therefore, in order to control the transport one needs to control the large events. Because SOC systems are intrinsically very resilient to perturbations a study of different types of perturbations has been made to determine which types can trigger or prevent these large transport events. Computational experiments with a sandpile model of SOC dynamics suggests some modification of the transport dynamics is possible with periodic perturbations of the internal sources and critical gradients. Triggering of large events can be achieved with short sharp perturbations while distributed small perturbations may be used to inhibit large events. In order to observe these effects in an intrinsically noisy system a set of statistical tests is also presented.