Optimizing particle transport for enhanced confinement in quasi-isodynamic stellarators.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 42141536.
- Also identified by DOI 10.1103/fbbl-ps5l.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Despite substantial advances in mitigating turbulent heat losses, including those achieved in the stable quasi-isodynamic design family [J. Plasma Phys. 89, 905890504 (2023)0022-377810.1017/S002237782300065X; PRX Energy 3, 023010 (2024)2768-560810.1103/PRXEnergy.3.023010], particle confinement remains a principal performance bottleneck in modern quasi-isodynamic stellarators, a challenge not fully addressed in previous optimization efforts. Using gyrokinetic simulations within the gene-Tango framework, we identify suppressed inward thermodiffusion, caused by unfavorable magnetic geometry, as the primary cause. To overcome this limitation, we design a new configuration with a reduced mirror ratio, which enhances the contribution of passing electrons to the inward particle flux. This facilitates the formation of strongly peaked density profiles, suppresses turbulence, and leads to a substantial improvement in confinement. Our optimized configuration achieves nearly a twofold increase in energy confinement compared to Stellaris, highlighting the crucial role of optimizing particle transport in next-generation stellarator designs.