Numerical investigations of detonation reinitiation and failure modes from Mach reflection

Conference item

In this study, the stoichiometric hydrogen-air mixture detonation wave formations following a Mach reflection of two incident shocks are numerically studied. Compressible Navier-Stokes equations for two-dimensional reactive flow are solved via a high order numerical algorithm and the chemical reaction follows a newly calibrated chemical-diffusive model (CDM). By arranging the obstacle at the mid-height of the channel, detonation waves go through the process of propagation-overdriven-diffraction and the repeatable Mach reflection of the incident shocks can be captured at the trailing edge of the obstacle. From different geometric parameters of the obstacle, we observe different detonation propagation modes after Mach reflection: detonation reinitiation characterized by the transverse detonation waves, decaying shock decoupled with flame, and inert shock with no ignition corresponding well to the experimental findings. Relying on the high resolution of the numerical simulations, we are able to obtain critical information about the detonation wave formation processes, and the corresponding detailed mechanisms are analyzed for various modes. In order to quantitatively analyze the critical conditions for detonation reinitiation, we adopted a theoretical D(κ) curve from the generalized ZND model based on the weakly-curved quasi-steady detonation by Kasimov and Stewart, which provides the relationship between critical detonation speed and curvature. Compared with different detonation modes in our simulations, the results show that D(κ) curve from the ZND model gives a good indication of the detonation reinitiation region in the distribution map of velocity and curvature. The results indicate the current model can accurately determine the wave formation following a Mach reflection of two incident shocks. Furthermore, this presents the first numerical simulation supporting the previous experimental studies in confirming hydrogen detonations are in good agreement with the critical curvature predicted by the laminar ZND theory.

Authors: Zhang, S; Lai, S; Tang, S; Yang, L; Qi, F

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Proceedings of the Combustion Institute
• Volume: 41
• Article number: 105948
• Publication date: 2025-10-28
• Acceptance date: 2025-10-02
• Event title: 15th Asia-Pacific Conference on Combustion (ASPACC 2025)
• Event location: Singapore
• Event website: https://www.aspacc2025.org/
• Event start date: 2025-05-18
• Event end date: 2025-05-22
• DOI: 10.1016/j.proci.2025.105948
• EISSN: 1873-2704
• ISSN: 1540-7489
• Language: English
• Keywords: Mach reflection; detonation wave; numerical simulation; weakly-curved quasi-steady detonation