Tools for MHD simulation of hot dense plasma

Abstract

The complexity of physical problems in plasma demands special tools for its analysis. The primary source of data is, of coarse, the physical experiment. But, sufficiently complete comprehension of physical phenomenon is actually impossible without the numerical simulation, which is more and more often named as computational experiment. Moreover, computational experiment usually provides more complete set of data, which becomes credible only after verification by experiment. The processes under consideration (such as different Z-pinches, plasma opening switches-POS, plasma focus and others) have some common features. Fist of all, they are non-stationary and subjected to divers instabilities. Another common feature is a big difference in time and spatial scales, and small local details are very often significant for global process development. This means, that some kind of adaptation is inevitable for numerical simulations. Traditional lagrangian approach can be also considered as adaptation, based on the mass, but it is not applicable to the problems with high level of convection or mixing. Two numerical methods for MHD plasma simulation and corresponding codes are presented here. The first code ASTRE uses original adaptive mesh refinement algorithm, the other one, Z+ is based on classical arbitrary lagrangian-eulerian algorithm. These two approaches are complimentary. Each of them has its own advantages and specific application domains, but each of them covers the majority of the problems under consideration.