Three-Dimensional Structures of H 2 /Air Oblique Detonation Waves

We present the first extensive cell-resolved three-dimensional simulations of abruptly transitioning H2/air oblique detonation waves (ODWs) using detailed kinetics. For the first time in literature, two configurations, namely a wedge-induced ODW and cone-induced ODW are systematically compared for their characteristic differences in morphology for the same mixture and thermochemical conditions. The simulations reveal that the transition type is retained between 2D and 3D and also across the geometry between the wedge and the cone for the current mixture. All configurations exhibit a characteristic multi-zone structure with well-defined transition points demarcating the various zones. Compared to 2D, all 3D configurations exhibit the presence of an extra zone compared to 2D in the downstream cellular region, where a systematic and gradual transition to the regular cellular structures from an initial chaotic irregular cellular structure is observed. Further investigation into the stabilization angles between the cone and wedge reveals that the cone-induced ODW is found to stabilize at a smaller angle compare to the wedge as a result of the curvature provided by the cone allowing a higher gas-expansion leading to lower post-shock temperatures.