The Physics Basis for a Q≈1 High-Field, Compact, Axisymmetric Mirror

Date
Sep 14, 2022, 4:00 pm5:15 pm
Location
MBG Auditorium and Online
Audience
General Public

Speaker

Details

Event Description

Wednesday - September 14, 2022 

4:00pm-5:15pm EDT - PPPL AUDITORIUM AND VIA ZOOM

Hosted by Anurag Maan

Professor Cary Forest
University of Wisconsin, Prager Professor of Experimental Physics

The Physics Basis for a Q≈1 High-Field, Compact, Axisymmetric Mirror*

A public-private team has been formed to pursue the axisymmetric mirror path to fusion: ARPA-E has funded the construction of an high temperature superconducting prototype called the Wisconsin HTS Axisymmetric Mirror (WHAM), that involves the UW Madison, a new startup company Realta Fusion, MIT and CFS. The 3 step development path begins with a small mirror, WHAM1.0, to establish MHD stable plasmas relying on vortex and FLR stabilization by fast ions of a high mirror ratio simple mirror, a reactor scale simple mirror WHAM++ that uses 100+ keV neutral beam injection to validate the confinement, macro and microstability in a simple mirror, and finally a tandem mirror that uses two WHAM++ configurations with ~1MeV, rf heated ions for the end plugs of a HTS Axisymmetric Magnetic Mirror Reactor (Hammir). This talk will review the physics basis for WHAM++ and address the TRLs for magnets, heating systems, MHD techniques, and microstability for mirror distribution functions. I will rely on bounce averaged drift kinetic/Fokker-Plank solutions for mirror confined fast ions that show Q>1 is achievable in a simple mirror with mirror ratio > 10. Direct energy recovery greatly improves prospects even for electrical breakeven. MHD stability will come from FLR stabilization for m>1, and plasma shaping, divertors, vortex and feedback stabilization at high β for m=1. Microinstabilty will rely upon sloshing ions and high mirror ratio. A direct energy convertor appropriate for the axisymmetric exhaust of the mirror should be capable of recovering more than 50% of the lost energy thereby increasing Q even further. Breakeven is possible even for small energy input (several MWs). Applications of WHAM++ include use as a blanket test facility, a minor actinide burner and as a source of efficient process heat. Power production for an industrial scale will be with Hammir.

*This work has been supported by ARPA-E, the Wisconsin Alumni Research Foundation and CFS.

To join via Zoom: 
https://pppl.zoom.us/j/361549769?pwd=R0d5d0hFUjZJNnBhRGR0RkszOGM1UT09
Meeting ID: 361 549 769
Passcode: colloquium

Sponsor
Anurag Maan