Transitions to electrochemical turbulence.

Nonlocal complex Ginzburg-Landau equation for electrochemical systems.

By means of an extended center-manifold reduction, we derive the nonlocal complex Ginzburg-Landau equation (NCGLE) valid for electrochemical systems with migration coupling. We carry out the stability analysis of the uniform oscillation, elucidating the role of the nonlocal coupling in electrochemical systems at the vicinity of a supercritical Hopf bifurcation. We apply the NCGLE to an experime...

Spectral condensation of turbulence in plasmas and fluids and its role in low-to-high phase transitions in toroidal plasma.

Transitions from turbulence to order are studied experimentally in thin fluid layers and in magnetically confined toroidal plasma. It is shown that turbulence self-organizes through the mechanism of spectral condensation in both systems. The spectral redistribution of the turbulent energy leads to the reduction in the turbulence level, generation of coherent flow, reduction in the particle diff...

Spectrally Condensed Fluid Turbulence and L-H Transitions in Plasma∗)

Recent experimental and theoretical studies of two-dimensional (2D) turbulence reveal that spectrally condensed turbulence which is a system of coupled large-scale coherent flow and broadband turbulence, is similar to plasma turbulence near the L-H transition threshold. Large condensate vortices fed via the turbulent inverse energy cascade, can control both the level of the broadband turbulence...

Suppression of turbulence at low power input in a model for plasma confinement transitions

Gonfinement Transitions in the H - l Heliac

Experiments at low magnetic field (< 0.2 T) in the H-1 heliac show transitions in confinement at low temperature and low heating power-50 kW. These transitions exhibit many of the features seen in L-H transitions in large tokamaks and stellarators: steepening of the density gradient, increases in the radial electric field, suppression of turbulence, and increased ion energies. Future experiment...