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In the IGNITEX device the plasma is surrounded by massive conducting material composed of several layers. From inside to outside the layers may be categorized as: first wall-vacuum vessel, poloidal field magnet system, inner toroidal field magnet region with slits and outer homogeneous toroidal field magnet region divided into twelve sectors. The 2-D finite element program PROTEUS is employed to study current induction and plasma equilibrium throughout the ignition discharge. Some modifications of the original code PROTEUS which permit the study of compact plasmas with strong wall coupling are described.The structure layers are simulated either as diffusive or as a set of electric circuits properly connected. Different resistivity models are considered. The calculations presented here show that the flux swing produced by the poloidal field (PF) coil system is enough to induce over 12 MA of plasma current and that a sequence of equilibrium configurations with elliptical cross sections can be obtained by properly choosing the waveforms of the PF system currents throughout the discharge of 10 seconds. The effects of the eddy currents on the discharge are dependent on the resistivities of the material and are substantial if the resistivities are low. Thus, the importance of a consistent equilibrium calculation coupling plasma, coils and structures is demonsirated.

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The time evolution of a plasma confined in a tandem mirror with thermal barriers has been studied. A physics model is given which describes the kinetic interactions in velocity space between the particles of the various plasma species that exist in each spatial region of the confinement, and the effects of a variety of particle and energy sources applied to the plasma. The analysis includes particle and energy rate equations for the various species determining the plasma confinement. The analysis also includes quasineutrality and ambipolarity conditions which define the ambipolar potential profile along the axis of the device as well as expressions for the passing particle densities in each region. This model describes in a self-consistent manner the time evolution of tandem mirror confinement with thermal barriers including the steady-state phase of operation. The resulting system of equations is solved numerically. The axicell MFTF-B configuration has been studied specifically. A possible startup scenario has been obtained. The results show the time sequence that must be followed to build up a plasma from given initial conditions to the steady-state phase by means of appropriately programmed particle and energy sources applied to the plasma.