09.09.2025 - 13:54:32

Cellular stability of hydrogen–oxygen detonation

A detonation cellular stability mechanism based on the dynamics of reactive decaying blasts is examined through detailed analyses of two-dimensional (2D) numerical simulations of hydrogen-oxygen detonations. Different from previous blast-based examinations, we resolve the transient process of decoupling between shock and reaction fronts in decaying blasts, and correlate the size of unburnt gas mixtures behind decaying shocks to that of the subsequent blast kernels.

The impact on the stability mechanism of (1) chemical kinetics, (2) diffusive processes, and (3) boundary conditions are examined through a series of simulations. At a dopant level, ozone is known to reduce ignition delay without altering thermodynamic properties of the mixture, enabling investigation of the impact of ignition kinetics on the cellular stability. The addition of ozone leads to a stronger coupling between shock and reaction fronts and stabilizes the blast kernel to a smaller size. The resulting global cell size reduction in the ozonated detonation is well described by the stability analysis and in agreement with experimental cell measurements reported in Crane et al., Combust. Flame 200 (2019) 44–52.