Results 61 to 70 of about 2,329 (224)

Coarse-grained gyrokinetics for the critical ion temperature gradient in stellarators

Physical Review Research, 2022
We present a modified gyrokinetic theory to predict the critical gradient that determines the linear onset of the ion temperature gradient (ITG) mode in stellarator plasmas.
G. T. Roberg-Clark, G. G. Plunk, P. Xanthopoulos   +2 more
doaj   +1 more source

MHD Convection with Joule Heating and Internal Heat Generation in a Two‐Layer Discretely Heated Chamber Partly Filled with Porous Medium

International Journal of Energy Research, Volume 2024, Issue 1, 2024.
The present research presents an innovative approach by integrating magnetohydrodynamic (MHD) flow with resistive heating, integrating a partly permeable layer and interior heat production to scrutinize natural convective flow within a square domain. It also examines both straight and wavy interfaces between the porous and fluid domains.
Nahid Hasan, Niloy Deb, Sumon Saha, Mohamed Zbair   +3 more
wiley   +1 more source

Ideal MHD stability calculations for compact stellarators

Stability results for high-n ideal local pressure-driven instabilities (ballooning and interchange: modes) are calculated from the COBRA and TERPSICHORE codes and compared for several low aspect ratio stellarators.
Fu, G. Y., Jimenez, J. A., Monticello, D. A., Subbotin, A. A., Mikhailov, M. I., Cooper, W. A., Reiman, A. H., Sanchez, R., Ku, L. P., Isaev, M. Y., Hirshman, S. P.   +10 more
core   +1 more source

MHD Stability Calculations of High-Beta Quasi-Axisymmetric Stellarators

, 1999
The MHD stability of quasi-axisymmetric compact stellarators is investigated. It is shown that bootstrap current driven external kink modes can be stabilized by a combination of edge magnetic shear and appropriate 3D plasma boundary shaping while ...
Fu, G. Y., al, et, Kessel, C., Redi, M. H., Ku, L. P., Pomphrey, N.   +5 more
core   +1 more source

Data for "Calculation of permanent magnet arrangements for stellarators: A linear least-squares method"

, 2020
Data associated with the paper "Calculation of permanent magnet arrangements for stellarators: A linear least-squares ...
Matt Landreman
core   +1 more source

Stellar coronae [PDF]

Symposium - International Astronomical Union, 1997
The last two decades have seen the emergence of a new field in stellar astrophysics, the study of stellar coronae mostly in X-ray domain. With the advent of soft X-ray imagery X-ray emission was found from many thousands of solar-like stars. I will summarize the most important findings of X-ray surveys of late type stars and put the results in the ...
openaire   +1 more source

Reduced electrostatic turbulence in the quasi-isodynamic stellarator configuration CIEMAT-QI4

Nuclear Fusion
CIEMAT-QI4 is a quasi-isodynamic stellarator configuration that simultaneously features very good fast-ion confinement in a broad range of β values, low neoclassical transport and bootstrap current, and ideal magnetohydrodynamic stability up to $\beta ...
J.M. García-Regaña, I. Calvo, E. Sánchez, H. Thienpondt, J.L. Velasco, J.A. Capitán   +5 more
doaj   +1 more source

Intrinsic Turbulence Stabilization in a Stellarator

Physical Review X, 2016
The magnetic surfaces of modern stellarators are characterized by complex, carefully optimized shaping and exhibit locally compressed regions of strong turbulence drive.
P. Xanthopoulos, G. G. Plunk, A. Zocco, P. Helander   +3 more
doaj   +1 more source

Boundary turbulence simulations of the optimized HSX stellarator and comparison with experiments

Nuclear Fusion
We present the first-ever full- $f$ , three-dimensional, two-fluid simulation of plasma turbulence based on the drift-reduced Braginskii equations in the optimized Helically Symmetric eXperiment (HSX) stellarator in its quasi-helical configuration.
Z. Tecchiolli, L. Da Silva, J. Loizu, D. Boeyaert, A. Wolfmeister, W. Guttenfelder, P. Ricci, N. Nikulsin, B. De Lucca, D. Mancini   +9 more
doaj   +1 more source

Stellar Chromospheres [PDF]

International Astronomical Union Colloquium, 1980
Important progress in our understanding of stellar chromospheres has occurred in the past few years as a result of new observations, developments in spectral line formation theory, and the application of that theory to the construction of detailed model chromospheres.
openaire   +1 more source