A multi-scale model for use in hydrodynamic simulations of impacts and hypervelocity penetrations into porous silica aerogel

Abstract

Low-density silica aerogel is an ideal material for capturing hypervelocity interplanetary dust. To investigate the behavior of hypervelocity shock waves at different particle velocities using silica aerogel densities ranging from 80 kg/m3 to 320 kg/m3, a multi-scale Smooth Particle Hydrodynamics (SPH) approach is employed. The simulation results demonstrate a good agreement with the macroscopic experimental findings across a wide range of particle velocities, from 0.5 km/s to 20 km/s, while considering the shock wave velocities of the porous material and their linear variation. In addition, simulations of pressure-specific volume curves were conducted using the microscopic model. According to the simulation results, we present a novel compression model of silica aerogel materials regarding the classical form of the P−V relationship for porous materials. Building upon the microscopic model, we propose a macroscopic equivalent model for dynamic compression of low-density aerogel, which is subsequently incorporated into the hydrodynamic calculation of interplanetary dust hypervelocity penetration into aerogel. The results of the simulation of hypervelocity penetration indicate that the multi-scale model presented in this work can be used to simulate the macroscopic mechanical behavior of aerogels in a non-uniform field.