[Everyone] Fwd: Plasma Seminar TODAY @ IDRE: Evolution of Zonal Flows from Turbulence in Confined Plasmas and Giant Planets

[Emmanuel V. Masongsong]

Sorry for all the spam, but there are lots of great talks today!

----- Forwarded Message -----
From: "Seth E Dorfman" <sethd at physics.ucla.edu>

Dear all,

We have a plasma seminar TODAY Friday, May 16th at 1PM at the IDRE 
Portal, 5628 Math Sciences Building.  Pizza is at 12:30PM in the same 
location.  Our speaker is Dr. Klaus Hallatschek of the Max Planck 
Institute for Plasma Physics and Technical University Munich, and his 
title and abstract are as follows:

"Evolution of Zonal Flows from Turbulence in Confined Plasmas and Giant 
Planets"

According to everyday experience, turbulence destroys large scale 
structures by subdividing them into successively smaller ones until they 
dissipate. A strikingly different behavior is exhibited by the seemingly 
utterly disparate cases of the convective turbulence in magnetized 
plasmas, such as tokamaks intended for nuclear fusion, and in giant gas 
planets, such as Jupiter: Small vortices merge into larger ones, 
eventually ending up in system spanning flows, which, in the case of 
Jupiter, cause the well known east-west stripe pattern. The common 
ingredient in the two systems is a strong alignment of the turbulent 
eddies respectively along the magnetic field and the axis of rotation. 
Computer simulations of the two systems show that despite the chaotic 
nature of the turbulence, the time evolution of the zonal flows itself 
is rather deterministic but varies qualitatively depending on the fully 
nonlinear properties of the turbulence, and can exhibit a memory effect. 
The flows in turn have repercussions for the turbulence as well, leading 
for instance to transport modulations in tokamaks and turbulence bursts 
in the giant planets. Apart from the commonalities between the two 
systems owing to the eddy alignment, there are also differences due to 
the complex geometry of confined plasmas, which imprints a 3D structure 
on the zonal flows and creates oscillating global flows.

http://www.pa.ucla.edu/sites/default/files/plasma_Hallatschek51614_flyer.pdf