Today - Invitation to the ICTP STI Colloquium by Francesco Volpe on "High-field stellarators with liquid metal walls", Friday 8 July 2022 at 4 p.m.

[STI Secretariat]

Dear All,

You are most cordially invited to the ICTP STI Colloquium by Francesco 
Volpe on "High-field stellarators with liquid metal walls", on *Friday 8 
July 2022* at 16:00 CEST in the *Budinich Lecture Hall,* and online.
*
Abstract*

After a reminder of basic notions of fusion and magnetic confinement of 
plasmas, the talk will present results and plans from the European 
start-up Renaissance Fusion. The company synergistically combines three 
main pillars: the stellarator, High Temperature Superconductors (HTS) 
and liquid metal walls. The stellarator magnetically confines fusion 
plasmas similarly to a tokamak, but without needing a current in the 
plasma. As a result it is more stable and inherently steady-state, but 
requires more complicated external coils. At Renaissance Fusion we 
dramatically simplify the coils by (1) finding solutions on simplified 
coil-winding-surfaces and by (2) streamlined manufacturing. Tapes and 
cables are bypassed. Instead, multiple layers of HTS material are 
directly deposited on the vacuum vessel or other wide surfaces, and 
patterned to impose specific supercurrent paths that generate 
stellarator magnetic fields. Both simplifications (1) and (2) pose 
interesting mathematical problems, for instance in inverse problems and 
optimization. Mesoscale liquid metal walls shield the stellarator and 
delicate HTS from neutrons and make them less radioactive. Experimental 
evidence will be presented of free-surface liquid metal flows adhering 
to the interior of cylindrical chambers by means of electromagnetic and 
centrifugal forces. Passive and active magnetohydrodynamic stabilization 
was obtained, as well as initial results toward feedback stabilization. 
Additional optimization results will be presented in the areas of coil 
force minimization, neutronic optimization of plasma-facing liquid metal 
walls, the design point of a profitable reactor and, in the shorter 
term, next-step HTS stellarator experiments. Paradigm-shifting ways of 
extracting Tritium will be presented. Research needs, job openings and 
areas of possible collaboration will also be discussed.

*Biosketch*

Francesco A. Volpeis a fusion plasma physicist turned entrepreneur. He 
studied and conducted his research in Italy (Laurea 1998), Germany (PhD 
2003), the UK and USA (post-docs ended in 2008). From 2009 to 2019 he 
held academic appointments at the University of Wisconsin, Madison, and 
at Columbia University, in New York, where he reached the rank of 
Associate Professor in 2015. Francesco conducted research on all four 
major magnetic confinement fusion concepts (tokamaks, spherical 
tokamaks, stellarators and reversed field pinches), making contributions 
to the physics of Electron Bernstein Waves, avoidance of tokamak 
disruptions, simplification of stellarators and control of liquid metal 
walls.

He received the 2003 Otto Hahn Medal (thesis prize of the Max Planck 
Society), the 2011 DOE Early Career Award and the 2015 Excellence in 
Fusion Engineering Award by Fusion Power Associates. In 2019 he earned 
an Executive MBA at ESCP Europe and in 2020 he founded the first 
magnetic fusion start-up in continental Europe and one of only two 
stellarator start-ups in the world: Renaissance Fusion.

For online participation, please register in advance at:
https://zoom.us/webinar/register/WN_RRol4rpoQu22YSsCEHBnSw 
<https://zoom.us/webinar/register/WN_RRol4rpoQu22YSsCEHBnSw>

The event will be followed by some light refreshments.


-- 
Nicoletta Ivanissevich (Ms.)
Secretariat,
STI - Science, Technology and Innovation Unit
The Abdus Salam International Centre for Theoretical Physics
Strada Costiera, 11
I-34151 Trieste
Italy

Phone: +39-040-2240.383
STI Webpage:https://www.ictp.it/research/sti.aspx
Email:sti at ictp.it

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