The role of the Yoshizawa effect in the Archontis dynamo

The Archontis dynamo has no helicity, but it generates a magnetic field that has cross helicity. Flows with cross helicity can generate large-scale magnetic field via the Yoshizawa effect if there is also mean vorticity in the flow.

Visualization of magnetic field Bz: mpg (42M)

In the example above, the box is 4 times bigger than one flow cell, so the domain size is (8π)3, the amplitude of the driving is 10-3, and ν=η=5×10-3. The resolution is 323 meshpoints.

Reference:

Sur, S., & Brandenburg, A.: 2009, ``The role of the Yoshizawa effect in the Archontis dynamo,'' Monthly Notices Roy. Astron. Soc. (submitted) (arXiv:0902.2394, HTML)
$Date: 2009-06-14 15:06:11 $, $Author: brandenb $, $Revision: 1.4 $