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Pressure profile

The pressure profile must always be specified, hence the following applies whether .

The pressure profile is chosen by setting the switches and in the input file. The value of the pressure on axis is give by in units of . Thus if then the value of on axis = . Note however that when the code is in the mode, then the field is reset internally to ensure that the stream function at the plasma edge. In this case the normalization of is reset at the end of the iteration procedure, and will not be exactly as indicated here. In this case it is necessary to rerun the equilibrium code to get a precise desired value after the normalization is determined.

In this option the pressure profile is determined by an analytic function, whose specific form is set through the value of . Generally we choose

Standard PEST profile.

In this option it is possible to reduce at the same rational surfaces where is reduced. The degree of reduction is determined by . At the present time the normalization is not well defined and values of can be greater than unity.

ORNL profile

In this form and are input. is determined internally to set the total plasma current, , which is in turn determined from .

Chebyshev - TRANSP profile.

where is an array of constant obtained from the file in a manner similar to the , described above. As before the are the Chebyshev polynomials and the coefficients are obtained from a DATA file:

      call link('unit11=(ppoly,open)//') 
2000  format(i2)
2100  format(1e12.5)

. In this option the pressure profile is obtained by interpolation from an array which is read from a file This option requires that . As before is set independently to fix on axis.

Note In addition, there is the possibility of generating a sequence of flux conserving equilibria using the profile from the base case( or ) by setting and . Then

Note The other values of invoke different forms of the pressure profiles, the details of which are in the source code. See and .

Next: profile Up: Profiles Previous: profile
Tue Nov 22 17:17:59 EST 1994