Effects of a non-monotonic safety factor on the particle transport and diffusion in the case of a reversed magnetic shear

2009 ◽  
Vol 76 (1) ◽  
pp. 29-37
Author(s):  
M. GHABBOURI ◽  
D. SAIFAOUI ◽  
A. BOULEZHAR ◽  
A. DEZAIRI ◽  
M. EL MOUDEN
Keyword(s):  
Safety Factor ◽  
Particle Transport ◽  
Numerical Study ◽  
Dominant Role ◽  
Magnetic Shear ◽  
Transport Barriers ◽  
Internal Transport Barriers ◽  
Transport And Diffusion ◽  
And Diffusion ◽  
Internal Transport

AbstractThis work is based on a numerical study of particle transport and diffusion using ITER parameters. In particular, the effects of introducing a non-monotonic safety factor (NMSF) in the case of a reversed magnetic shear are shown. These results are compared with those found by using a monotonic safety factor (MSF). Double internal transport barriers are detected influencing the transport and diffusion of particles. The choices of the mode (m, n) and the m/n values play a dominant role for the particle diffusion, which leads to an improvement of the magnetic confinement.

scholarly journals Suppressing electron turbulence and triggering internal transport barriers with reversed magnetic shear in the National Spherical Torus Experiment

2012 ◽  
Vol 19 (5) ◽  
pp. 056120 ◽  
Author(s):  
J. L. Peterson ◽  
R. Bell ◽  
J. Candy ◽  
W. Guttenfelder ◽  
G. W. Hammett ◽  
...  
Keyword(s):  
Spherical Torus ◽  
Magnetic Shear ◽  
Transport Barriers ◽  
Internal Transport Barriers ◽  
Internal Transport

Toroidal equilibrium states with reversed magnetic shear and parallel flow in connection with the formation of Internal Transport Barriers

2015 ◽  
Vol 81 (4) ◽  
Author(s):  
Ap. Kuiroukidis ◽  
G. N. Throumoulopoulos
Keyword(s):  
Magnetic Field ◽  
Linear Stability ◽  
Current Density ◽  
Sufficient Condition ◽  
Magnetic Shear ◽  
Transport Barriers ◽  
Internal Transport Barriers ◽  
The Stability ◽  
The Magnetic Field ◽  
Internal Transport

We construct nonlinear toroidal equilibria of fixed diverted boundary shaping with reversed magnetic shear and flows parallel to the magnetic field. The equilibria have hole-like current density and the reversed magnetic shear increases as the equilibrium nonlinearity becomes stronger. Also, application of a sufficient condition for linear stability implies that the stability is improved as the equilibrium nonlinearity correlated to the reversed magnetic shear gets stronger with a weaker stabilizing contribution from the flow. These results indicate synergetic stabilizing effects of reversed magnetic shear, equilibrium nonlinearity and flow in the establishment of Internal Transport Barriers (ITBs).

scholarly journals Перенос тепла и частиц в начальной фазе омических разрядов сферического токамака Глобус-М

2019 ◽  
Vol 45 (13) ◽  
pp. 17
Author(s):  
А.Ю. Тельнова ◽  
Г.С. Курскиев ◽  
Н.Н. Бахарев ◽  
В.К. Гусев ◽  
Е.О. Киселев ◽  
...  
Keyword(s):  
Electron Temperature ◽  
Safety Factor ◽  
Initial Conditions ◽  
Transport Processes ◽  
Density Peak ◽  
Transport Barriers ◽  
Internal Transport Barriers ◽  
Plasma Core ◽  
Internal Transport ◽  
Electron Density Peak

AbstractThe results of experiments and simulations of the transport of heat and particles in the Globus-M spherical tokamak are presented. Investigations were carried out in the ohmic mode in hydrogen and deuterium plasma. It is shown that in the phase of current growth under the same initial conditions, as long as the condition is met at which the minimum of the safety factor exceeds unity, two scenarios of discharge development are possible: with an electron temperature dive or with an electron density peak. After the safety factor reaches the value of 1, the differences are no longer observed. Modeling of transport processes using the ASTRA code showed that the dive of the electron temperature and density is a consequence of the decrease in the transport of heat and particles in the plasma core (i.e., the presence of internal transport barriers).

Physics of strong internal transport barriers in JT-60U reversed-magnetic-shear plasmas

2006 ◽  
Vol 48 (5A) ◽  
pp. A55-A61 ◽  
Author(s):  
N Hayashi ◽  
T Takizuka ◽  
Y Sakamoto ◽  
T Fujita ◽  
Y Kamada ◽  
...  
Keyword(s):  
Magnetic Shear ◽  
Transport Barriers ◽  
Internal Transport Barriers ◽  
Internal Transport
Sign in / Sign up

Export Citation Format

Share Document