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| Two-dimensional, time-dependent, reactive Navier–Stokes equations involving the effects of viscosity, thermal conduction, molecular diffusion and turbulence etc. were solved to obtain a deep insight into gaseous detonation vortex-like structures and its induced mechanism. Detailed chemical reaction model, together with standard k-εturbulence model, was employed in this paper. Numerical simulation indicates that a large amount of vortex-like structure emerges in detonation flow field due to its intrinsic three-dimensional structure. Vortex-like structure can also be induced by wall geometry with an abrupt cross-section area change. Shock wave interacts with slip line, which in turn causes the formation of vortex-like structure. In nature, all these induce the instability of slip line, so it is the slip line instability that is the essential reason for the emergence of vortex-like structure. Additionally, the difference of vortex-like structure between an ordinary detonation and a marginal detonation was compared. In an ordinary detonation, the vorticity magnitude of vortex-like structure is different, even for two vortex-like structures in the same pair. With increasing the distance away from leading front, the vorticity magnitude gradually decays. Slip line in a marginal detonation is more unstable and produces more vortex-like structures. |
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| Keywords:Gaseous detonation wave;Vortex-like structure;Slip line;Detailed chemical reaction model;Numerical simulation |
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