Modeling Damage Induced Initiation of Explosives

Sandia National Laboratories developed the DaMaGe Initiated Reaction (DMGIR) model to numerically predict weakly supported shock waves that generate an initiation at energy levels below the shock-to-detonation transition (SDT) of an explosive. The DMGIR model couples the strain energy fluence contribution from damage to the initiation process. It does not attempt to include all possible specific initiation mechanisms at the mesoscale, but instead looks at cumulative damage incurred in the explosive through experimental calibration of a small number of material constants. Both shock pressure (hydrostatic) and shear stress (deviatoric) are accounted for in the summation. The model was designed to be robust and relatively simple to calibrate. The DMGIR model is implemented into the Sandia National Laboratories’ CTH shock wave and large deformation code. The model runs concurrently with the existing History Variable Reactive Burn (HVRB) model currently used for shock initiation.