The gas gun launch advances in numerical simulation of hypervelocity impact

Abstract

In the experimental researches of spacecraft shield structure, it is necessary to launch metal flyers with mass of gram-order to hypervelocity about 10 km/s. Researchers in Institute of Fluid Physics of CAEP have already made a breakthrough of this key technique on the two-stage light gas gun facility. Under laboratory conditions, a LY12 aluminum flyer with mass of gram-order can be driven and accelerated to 11.0 km/s, and Ta and Pt metal flyers with same mass magnitude and higher densities to 10.0 km/s and 9.0 km/s, respectively. Further development on experimental techniques to drive flyers to even higher velocity is expected. In this paper, numerical simulations based on MFPPM code with high order scheme for the process of driving flyers to hypervelocity through gas gun facility are performed. The calculation result of velocity profile of the flyer free surface agrees well with experimental data measured through DISAR. To simulate melting, gasification, plasma changing and other phenomena appearing in hypervelocity impacts, the elastic-plastic hydrodynamics code LSFC in Eulerian frame with independent intellectual property is also developed. Primary numerical simulation for the same problem is carried out. The results of two codes are in excellent agreement. In future work, LSFC code will be further developed to carry out numerical simulation analysis for hypervelocity impacts of space debris and design of shield structures. hypervelocity flyer, hypervelocity impacts, light gas gun facility, MFPPM, LSFC