DTRA-funded Turbulence Modeling Algorithms Improve ALE3D, the Lawrence Livermore National Lab Hydrocode for Simulation of Post-blast Agent Dispersion

Problem: Before directing a conventional weapon on a weapon of mass destruction (WMD) target, it is necessary to simulate the weapon effect to ensure that the weapon will completely eliminate the WMD in the target. This is especially important in the case of targets containing biological agents because biological agents can be spread from person to person to those who were not in direct contact with the target or post-blast plume. Therefore, it is important to neutralize bio-agents in a WMD before they come in contact with any humans. DTRA has funded basic research to model the post-detonation survival of spores and particles in order to identify conditions for spore neutralization.


Spores dispersed and neutralized by explosive charge.

Results: Professor Suresh Menon of Georgia Tech has developed new, multi-scale, multi-phase turbulence algorithms to model blast waves with reactive particles. The model enables spore survivability and neutralization analyses with Monte Carlo-based uncertainty quantification for particles of multiple chemical and physical properties in different operational environments. Results showed that spore neutralization depends strongly on the distance from the charge. Initial concentration and thickness have minimal effect in dilute limit and long term survival is based on location in the mixing zone.

Potential: This model contributes to an overall understanding of plume dynamics and may assist in the design of WMD-defeat weapon charges that will eliminate the risk of exposure to WMDs resulting from post-detonation dispersion.

Transition/Impact: The Georgia Tech turbulence model has been incorporated into Lawrence Livermore National Laboratory’s ALE3D hydrocode for modeling the dynamic behavior of explosives detonation including heat conduction, chemical kinetics and species diffusion, incompressible flow, using a wide range of material models, chemistry models, multi-phase flow, and magneto-hydrodynamics for long (implicit) to short (explicit) time-scale applications. The ALE3D code is a single code that integrates many physical phenomena. It is in widespread use within the counter-WMD community to model explosive blasts and simulate weapon damage effects.



WEAPON AND WMD TARGET INTERACTION (TA-4)
HDTRA1-10-1-0008: MODELING TURBULENT MIXING/COMBUSTION OF BIO-AGENTS BEHIND DETONATIONS: EFFECT OF INSTABILITIES, DENSE CLUSTERING, AND TRACE SURVIVABILITY
SURESH MENON, GEORGIA TECH