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Abstract. The principle of minimum dissipation rate subject to helicity and energy balance is applied to tokamak with arbitrary aspect ratio. For a set of given parameters and boundary conditions, the self-consistent solutions of whole resulted Euler-Lagrange equations as well as both helicity and energy balance equations are obtained numerically in cylindrical coordinate with cross section assumed a rectangle. Applied electric field and boundary toroidal magnetic field is assumed to be in inverse proportion to r. We found that the minimum dissipation states give some typical current profile modes and some forms are obtained in recent experiments. Each current profile modes are achieved by adjusting controllable parameters such as plasma resistivity, boundary toroidal magnetic field or boundary electric field. Here we present two typical theoretical forms for NSTX dimensions. One peaks in edge region of high field side and the other peaks in central region on equatorial plane. We also obtained the current profile with reversed shear and the current may have a hole or even reverse in the central part in some parameter regions as shown in paper.
IAEA 2003
