Shock-induced hotspot formation and chemical reaction initiation in PETN containing a spherical void

摘要

We present results of reactive molecular dynamics simulations of hotspot formation and chemical reaction initiation in shock-induced compression of pentaerythritol tetranitrate (PETN) with the ReaxFF reactive force field. A supported shockwave is driven through a PETN crystal containing a 20 nm spherical void at a sub-threshold impact velocity of 2 km/s. Formation of a hotspot due to shock-induced void collapse is observed. During void collapse, NO_2 is the dominant species ejected from the upstream void surface. Once the ejecta collide with the downstream void surface and the hotspot develops, formation of final products such as N_2 and H_2O is observed. The simulation provides a detailed picture of how void collapse and hotspot formation leads to initiation at sub-threshold impact velocities.