We present a molecular dynamics simulation of a Mach 5 reactive shock wave in a stoichiometric gaseous ${\mathrm{H}}_2/{\mathrm{O}}_2$ mixture. ${\mathrm{H}}_2$ is compressed slightly ahead of ${\mathrm{O}}_2$ to form two separate shock fronts. Chemical reactions initiate during the ${\mathrm{O}}_2$ compression, followed by a postdetonation flow exhibiting a Zeldovich–von Neumann–Döring-like structure. To analyze the shock substructure, the profiles of state variables near the shock and the postshock particle velocities of molecules are compared with those of a synthetic, inert shock wave. The results indicate that the small ${\mathrm{H}}_2$ to ${\mathrm{O}}_2$ mass ratio causes the separation of shock fronts regardless of chemistry, like those observed in rarefied binary gases, and the velocities of the species relax before leaving the shock region, characterizing the nonequilibrium ${\mathrm{H}}_2/{\mathrm{O}}_2$ shock dynamics so that reactions are present but not as active as they were without the separation.

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• Combustion
• Detonation
• Molecular dynamics
• Shock waves