Review of the Forest fire model for high explosives

Abstract

Forest fire is a burn model for reactive hydro simulations that is widely used to describe both initiation and propagation of detonation waves in solid high explosives. Here we thoroughly review the assumptions of the model. In analogy with Whitham-Chisnell shock dynamics, we derive the Forest fire rate based on a characteristic analysis of a shock-to-detonation transition. Code issues with implementing the Forest fire model are also discussed. The analysis leading to the Forest fire rate is more general than the simplifying assumptions used by the model. The Forest fire analysis provides important constraints needed for any burn model to fit shock initiation data. This data is fundamental to ignition sensitivity of high explosives.

Second shock ejecta measurements with an explosively driven two-shockwave drive

“…[40][41][42] The materials EOSs used a two-phase EOS for Sn ("ptran" in CTH that simulates the bto c-Sn transition), a Mie-Gr€ uneisen EOS 43,44 for Ta and acetal (we substituted PMMA for acetal in the simulation), and a SESAME lookup table 45 for Ti. The elastic-plastic properties were simulated with a Steinberg-Guinan-Lund viscoplastic model 46,47 for Sn and Ti, and we let the PMMA (acetal) plastically flow.…”

Shock to Detonation Transition of Plastic Bonded Aluminized Explosives

“…Comparing shock velocity between shots is more relevant than the x-t diagram. Figure 5 illustrates the idea of the single curve initiation (SCI) initially proposed by Lindstrom and then reviewed by Menikoff [15]. SCI theory puts forward that each high explosive has a unique acceleration function that drives the shock to detonation.…”

“…The mass fraction of aluminum particles is constant and equal to the one of PBXN109-FR high explosive. The mixtures variables are calculated thanks to the constitutive relations (9) and (14)(15)(16)(17). The additional terms in the divergence of momentum and energy balance equations are called non-equilibrium terms.…”

Burn front and reflected shock wave visualization in an inertially confined detonation of high explosive

“…The abovementioned simulations were carried out at 200 μm resolution. Finally, we ran simulations with the Forest fire (FF) reactive burn model [3] at several mesh resolutions from 500 to 150 μm. For the same burn model, Fig.…”