Three-dimensional modeling of inert metal-loaded explosives

The reactive three-dimensional hydrodynamic code 3DE has been used to investigate the reactive hydrodynamics of a matrix of tungsten particles in HMX. A propagating detonation proceeding through the matrix of tungsten particles gives calculated detonation velocities and pressures that are much higher than observed. If the heterogeneous shock initiation Forest Fire rate for HMX is used to describe the reactive kinetics, some of the individual detonation wavelets between the tungsten particles fail. The shocked explosive continues to decompose and release energy after shock passage. Equations of state are described for a tungsten and a leadloaded explosive that reproduce the observed performance of these nonideal explosives. The calibrated equations of state use a partial energy release suggested by the three-dimensional model. Evidence is presented that the explosives have a flat top Taylor wave characteristic of weak detonations.