Page 38 - Fundamentals of Magnetic Thermonuclear Reactor Design

Facilities With Magnetic Plasma Confinement Chapter | 2 21

FIGURE 2.11 Plasma energy confinement time: experimental data and the H-mode scaling
results. (Copyright ITER Organization, 2017).

The stability margin q is generally taken to be greater than or equal to 3. This is
95
sufficient to have a plasma discharge with a low probability of a current disruption.
In the case of DT plasma, to close-up the equation system, physical parameters
should be complemented with several engineering ones. They include the following:
l neutron first-wall load (p ),
n
l duration of plasma inductive burning stage (∆t burn ), and
l gap between the plasma column and the inner part of the TF coils (∆ PL–TF ).
As a result, the geometry, plasma current, toroidal magnetic field and other
tokamak parameters become determined. The limit values of the MFR’s physi-
cal and engineering parameters shown in Table 2.5 can be divided into the fol-
lowing three groups:
l Purely physical parameters (β , H , C ) that can only be achieved, if new
y,2
ne
N
physical ideas come up.