The 4th International Conference on Matter and Radiation at Extremes (ICMRE 2019)

380 / 2019-02-28 15:59:18

Numerical and Experimental Study On Richtmyer-Meshkov instability of Metal-Gas/Vacuum Interface at extreme compressing conditions

Richtmyer-Meshkov instability, extreme compress, ionization

Plenary track > Interface Instabilities at Extremes

Richtmyer-Meshkov instability(RMI) which induced by shock impacting corrugated interface exists widely in Inertial Confinement Fusion, Supersonic Combustion, Supernova Remnants etc. It is of great significance in engineering and science to investigate the RMI when loading strength is increased from low energy density state to high energy density state. RMI of Li-H2 interface under high energy state had been studied with electric force field (eFF) molecular dynamics in nano scales. The results reveal that the length of linear region and the amplitude of the nonlinear region are promoted under high energy density state by the ambipolar acceleration induced by the extra electric field due to the electron/ion separation under extreme shock conditions[1]. In order to confirm such a mechanism in macro scale, experiments were performed on two/three stage light gas gun. Tin-vacuum interface was impacted by flyer with velocity ranging from 2 km/s to 10 km/s. A kind of similar interface acceleration evolution are observed evidently in high energy density loading state. The results were further compared and the mechanism differences between nano scale and macro scale were discussed.