Reply To: How LPPX could overcome the Dynamical neutron saturation?

[jamesr]

MTd2 wrote:

Basically this give a limit on the current a filament can carry where the radiation pressure outwards balances the pinch force inwards. For deuterium the figure is around 1.6MA.

According to Sing Lee, this limit is due the impedance of the contracting plasma not due radiation pressure.

It can be overcome by increasing the voltage between the cathodes to high values, like above 90KV:

http://www.plasmafocus.net/IPFS/2010 Papers/2010 Pp2 IJER.doc

The Las Vegas DPF can do that:

https://focusfusion.org/index.php/site/article/july_switch_update/

Unfortunately, LPPX cannot…

The 1.6MA figure is a generic limit for a single current carrying filament of plasma (a Z-pinch) regardless of its size or origin.
The particular geometrical & electrical arrangement of a DPF is the topic of Sing Lee’s paper. The Pease-Braginskii current is not a hard limit, in that is cannot be exceeded. It is just that if the current is higher than the critical value for that fill gas, the filament will be unstable and begin to collapse because the pressure is no longer balanced.