Abstract
A minimum set of equations based on the peeling-ballooning (P-B) model with nonideal physics effects (diamagnetic drift, drift, resistivity, and anomalous electron viscosity) is found to simulate pedestal collapse when using the new BOUT++ simulation code, developed in part from the original fluid edge code BOUT. Nonlinear simulations of P-B modes demonstrate that the P-B modes trigger magnetic reconnection, which leads to the pedestal collapse. With the addition of a model of the anomalous electron viscosity under the assumption that the electron viscosity is comparable to the anomalous electron thermal diffusivity, it is found from simulations using a realistic high-Lundquist number that the pedestal collapse is limited to the edge region and the edge localized mode (ELM) size is about 5%–10% of the pedestal stored energy. This is consistent with many observations of large ELMs.
- Received 25 May 2010
DOI:https://doi.org/10.1103/PhysRevLett.105.175005
© 2010 The American Physical Society