Modeling HE Detonation Muller, Shepherd, Chakraborty, Dasgupta, Goddard Provide a detailed reaction mechanism: 72 Species 445 Reactions Ultimately reduce (Eckett) Understand detonation on a reaction by reaction basis Understand how additional species (binder, aging, etc.) alters detonation properties. HMX

Starting Points GRI nitromethane mechanism 49 species 300 reactions Melius nitromethane mechanism 27 species 130 reactions Yetter RDX mechanism 48 species 240 reactions Guirguis nitromethane mechanism & data Chakraborty/Lin reaction modeling

Additional Species

Thermochemical Data B3LPY/6-31G** calculation Compute Cp, H, S from 300-6000 K Fit to 14-term NASA form

HMX/RDX Combustion

Validation: Nitromethane Shock Data

Chemkin with Correct EOS CV uses Ideal Gas EOS Can’t describe high P,T Obtained CK-Real Gas BKW, vdW, Peng-Robinson BKW EOS:

DFT-MD Modeling of HE Initiation Understand how mechanical energy is transormed into chemical energy Hypothesis that the H atoms are displaced more by the shock wave than the heavy atoms. Run DFT/MD to investigate this.

Mechanism Dimethyl nitramine

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