Enhanced performance in quasi-isodynamic max-$J$ stellarators with a turbulent particle pinch

G. G. Plunk; A. G. Goodman; P. Xanthopoulos; P. Costello; H. M. Smith; K. Aleynikova; C. D. Beidler; M. Drevlak; S. Stroteich; P. Helander

arXiv · 2507.19319

Enhanced performance in quasi-isodynamic max-$J$ stellarators with a turbulent particle pinch

G. G. Plunk·A. G. Goodman·P. Xanthopoulos·P. Costello·H. M. Smith·K. Aleynikova·C. D. Beidler·M. Drevlak·S. Stroteich·P. Helander

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Abstract

Recent stellarator reactor designs demonstrate mostly outward turbulent particle transport, which, without advanced fueling technology, inhibits the formation of density gradients needed for confinement. We introduce ``SQuID-$\tau$'', a self-fueling quasi-isodynamic stellarator capable of sustaining density peaking through inward particle transport caused by turbulence. Temperature and density profile predictions based on high-fidelity gyrokinetic simulations demonstrate enhanced performance, significantly relaxing constraints on the size and magnetic field strength for reactor designs.

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G. G. Plunk, A. G. Goodman, P. Xanthopoulos, P. Costello, H. M. Smith, K. Aleynikova, C. D. Beidler, M. Drevlak, S. Stroteich, P. Helander. 2025-07-25. Enhanced performance in quasi-isodynamic max-$J$ stellarators with a turbulent particle pinch. https://arxiv.org/abs/2507.19319

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