Speaker
Description
See the full abstract here http://ocs.ciemat.es/EPS2019ABS/pdf/P5.2002.pdf
The results of plasma compression studies of nested wire and fiber arrays with current flowing through them are presented in this work. Experiments were made on the Angara-51 installation with current up to 4 MA. The current implosion of nested arrays represents a unique opportunity to simulate the interaction of a plasma flow with a magnetic field. Inside the volume of such an array, there is a collision of the supersonic plasma flow from the external wire array produced by the current flowing through it with the magnetic field generated by a part of the total discharge current flowing through the inner array. Various plasma flow regimes in the space between the inner and outer arrays were obtained: subAlfven (V_r<V_A), super-Alfven (V_r > V_A) and the regime with the formation of a transition region: a shock wave (SW) between the arrays, depending on the ratio of the radii of the nested arrays. The dependence of these flow regimes on the plasma formation rate of the inner and outer arrays is shown. The obtained experimental results are compared with the simulations of the plasma motion between the arrays using the three-dimensional radiationmagnetohydrodynamic code MARPLE. A possible scenario for the interaction of plasma in the nested arrays is proposed. At certain parameters of the nested arrays, a shell, quasiclosed in the azimuthal direction, is formed around the inner array. At the same time, the plasma of the outer array surrounds the inner one and stabilizes its compression. The suppression of MRT instabilities during plasma compression of the inner array leads to the formation of a stable, compact Z-pinch and the generation of a short-time soft X-ray pulse. Further optimization of the parameters of the nested arrays of mixed composition will be carried out by reducing the fraction of current flowing through the trailing mass by varying the number of fibers and their mass in the outer array. The research is carried out using the equipment of the shared research facilities of HPC computing resources at Lomonosov Moscow State University and supercomputers at Joint Supercomputer Center of the RAS (JSCC RAS).
This work was carried out with the partial financial support of the Russian Foundation for Basic Research under grants No. 18-29-21005, No. 18-02-00170.
