Recent Progress in MHD Stability Calculations of Compact Stellarators
Abstract
A key issue for compact stellarators is the stability of beta-limiting MHD modes, such as external kink modes driven by bootstrap current and pressure gradient. We report here recent progress in MHD stability studies for low-aspect-ratio Quasi-Axisymmetric Stellarators (QAS) and Quasi-Omnigeneous Stellarators (QOS). We find that the N = 0 periodicity-preserving vertical mode is significantly more stable in stellarators than in tokamaks because of the externally generated rotational transform. It is shown that both low-n external kink modes and high-n ballooning modes can be stabilized at high beta by appropriate 3D shaping without a conducting wall. The stabilization mechanism for external kink modes in QAS appears to be an enhancement of local magnetic shear due to 3D shaping. The stabilization of ballooning mode in QOS is related to a shortening of the normal curvature connection length.
- Authors:
- Publication Date:
- Research Org.:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Org.:
- USDOE Office of Energy Research (ER) (US)
- OSTI Identifier:
- 768647
- Report Number(s):
- PPPL-3505
TRN: US0005773
- DOE Contract Number:
- AC02-76CH03073
- Resource Type:
- Conference
- Resource Relation:
- Conference: 18th International Atomic Energy Agency's (IAEA) Fusion Energy Conference (FEC-2000), Sorrento (IT), 10/04/2000--10/10/2000; Other Information: PBD: 15 Nov 2000
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 29 ENERGY PLANNING, POLICY AND ECONOMY; BOOTSTRAP CURRENT; IAEA; NUCLEAR ENERGY; PRESSURE GRADIENTS; ROTATIONAL TRANSFORM; STABILITY; STELLARATORS; THERMONUCLEAR REACTORS
Citation Formats
Fu, G Y, Ku, L P, Redi, M H, Kessel, C, Monticello, D A, Reiman, A, Cooper, W A, Nuehrenberg, C, Sanchez, R, Ware, A, Hirshman, S P, and Spong, D A. Recent Progress in MHD Stability Calculations of Compact Stellarators. United States: N. p., 2000.
Web.
Fu, G Y, Ku, L P, Redi, M H, Kessel, C, Monticello, D A, Reiman, A, Cooper, W A, Nuehrenberg, C, Sanchez, R, Ware, A, Hirshman, S P, & Spong, D A. Recent Progress in MHD Stability Calculations of Compact Stellarators. United States.
Fu, G Y, Ku, L P, Redi, M H, Kessel, C, Monticello, D A, Reiman, A, Cooper, W A, Nuehrenberg, C, Sanchez, R, Ware, A, Hirshman, S P, and Spong, D A. 2000.
"Recent Progress in MHD Stability Calculations of Compact Stellarators". United States. https://www.osti.gov/servlets/purl/768647.
@article{osti_768647,
title = {Recent Progress in MHD Stability Calculations of Compact Stellarators},
author = {Fu, G Y and Ku, L P and Redi, M H and Kessel, C and Monticello, D A and Reiman, A and Cooper, W A and Nuehrenberg, C and Sanchez, R and Ware, A and Hirshman, S P and Spong, D A},
abstractNote = {A key issue for compact stellarators is the stability of beta-limiting MHD modes, such as external kink modes driven by bootstrap current and pressure gradient. We report here recent progress in MHD stability studies for low-aspect-ratio Quasi-Axisymmetric Stellarators (QAS) and Quasi-Omnigeneous Stellarators (QOS). We find that the N = 0 periodicity-preserving vertical mode is significantly more stable in stellarators than in tokamaks because of the externally generated rotational transform. It is shown that both low-n external kink modes and high-n ballooning modes can be stabilized at high beta by appropriate 3D shaping without a conducting wall. The stabilization mechanism for external kink modes in QAS appears to be an enhancement of local magnetic shear due to 3D shaping. The stabilization of ballooning mode in QOS is related to a shortening of the normal curvature connection length.},
doi = {},
url = {https://www.osti.gov/biblio/768647},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Nov 15 00:00:00 EST 2000},
month = {Wed Nov 15 00:00:00 EST 2000}
}