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Supercomputer simulations are of fundamental importance for understanding the physics of nonlinear processes in high temperature pulse plasma. The development of predictive codes is an urgent problem in computational plasma physics, as well as many other fields of science. Radiative magneto-hydrodynamics 3D code MARPLE is a full-scale multiphysics research code using the state-of-the-art physics, mathematics, and numerics as well as the up-to-date high performance computing functionality. Scalability study demonstrated that the code can fit existing petaFLOPS supercomputers as well as next-generation exaFLOPS ones. The code is currently used for multiphysics simulations, specifically for high energy density plasma in pulsed-power facilities. Compression of a wire array by a high-current discharge is a valuable tool for fundamental study of matter in extreme states. Different configurations of wire arrays were investigated numerically. A series of high resolution computations helped to create a very compact spherical bright radiation source using dedicated design of the electrodes, the wire array, and the mass distribution along the wires.

The project BELLA (LBNL, USA) is aimed to create an experimental facility for further advancing the development of laser-driven electron acceleration1. BELLA's unique attribute is the ability to use laser light to accelerate an electron beam up to 10 GeV level in a comparatively short distance of approximately one meter. The acceleration takes place during the propagation of a high power femtosecond laser pulse in the plasma formed in a capillary discharge. This capillary plasma forms a plasma channel able to guide the laser pulse, which in its turn forms a plasma wake wave that accelerates the injected electrons.

A design of fast current switch using wire explosion is a problem of studying by our team experimentally and numerically. The main unit of the experimental setup represents itself two coaxial cylindrical electrodes connected by a thin single wire which is exploded by the current pulse. In the experiments a current with the amplitude up to 80 kA and rise time of 7 μs flowing through the 4-mm tungsten wire. Plasma generated by exploded wire fills the inter-electrode space "circularly" owing to the interaction with magnetic field (up to 30 kG) produced by an external source and directed along the electrodes. The setup construction allows us to change the amplitude of current flowing between the electrodes and to measure the total resistance of inter-electrode volume. Therefore we can study a plasma dynamics by varying the current value. In our experiments the current amplitude is changed in a rather wide range of 10–80 kA, and a current rise time is changed from 109 to 1010 A/s. The experimental data are compared with those obtained via computer simulation carried out by means of the radiative magnetohydrodynamic code MARPLE3D (KIAM RAS). W e studied 3D plasma dynamics numerically (i) at a stage of a wire explosion and filling of the inter-electrode gap by plasma, and (ii) a stage of a plasma switch functioning. Numerical simulations allow to estimate a time which need to fill the volume between the coaxial electrodes with the plasma generated from the wire and to study the switch dynamics dependence on the hydromagnetic instability as well as on the Hall effect. The numerical data correlates with experimental results. The main problems we discuss are: (i) what are possible reasons of the rapid decreasing of the switch resistance and (ii) how we can maintain an appropriately high resistance of the switch during the time needed for its applications.