1 - Nuclear Sciences and Applications - IAEA

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200 -
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IAEA-CN-50/E-IV-7 741
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Z 2 MW
^~\ Qinp=10MW
\5MW
\n = 3X10 12 cm- 3
Qinp " 5 MW
^ \ n = 6X10 12 cm' 3
- - - - - _
1
1
50 100
FIG. 1. Electron temperature Te as a function of vertical field Bven for the case with R = 5 m,
a = J.5 m.
As shown in Ref. [7], when the plasma pressure is not too high and satisfies
the inequality
2 vert
a
a transverse diffusive flow with the diffusion coefficient 2)± = p| cei (B,,/Bven) 2
emerges along with a longitudinal plasma spread along the magnetic field lines with
the speed of sound, cs. Here pe is the Larmor radius of electrons and vei is the frequency
of electron-ion collisions. With an increase in the input power Qinp condition
(4) can be violated. Then the plasma losses from the system turn out to be
disastrously large and are determined by a transverse escape with a speed of about
Va/R cs [8]. In this case, the plasma pressure is actually, given by inequality (4)
(4)