Numerical investigations of detonation reinitiation and failure modes from mach reflection

Journal article

This work demonstrates numerical investigations of stoichiometric hydrogen-air detonation ignition behaviors following a Mach reflection of two incident shocks. Compressible Navier-Stokes equations for two-dimensional reactive flow are solved via a high order numerical algorithm and the chemical reaction follows a calibrated chemical-diffusive model (CDM). A diamond-shaped obstacle is placed at the middle of the channel, creating a converging-diverging cross section, where the detonation waves go through an overdriven-diffraction process. With different converging angles, a Mach reflection of the incident shocks is captured at the trailing edge of the obstacle, accompanied by three distinct detonation propagation modes: detonation reinitiation mode characterized by the transverse detonation waves, shock-flame decoupling mode, and fully quenched mode characterized by an inert shock with no ignition, all of which correspond well with earlier experimental findings. In order to fundamentally understand the reason behind these distinct detonation propagation behaviors and to uncover the critical conditions for detonation reinitiation, two theoretical approaches, including the D(κ) curve from the generalized ZND model based on the weakly-curved quasi-steady detonation by Kasimov and Stewart, as well as the critical decay rate model by Eckett et al. are adopted. The results show that the D(κ) curve from ZND model provides a reliable indicator for identifying the detonation reinitiation region in the velocity-curvature distribution map, while the critical decay rate model effectively distinguishes between ignition and complete quenching. This work presents the first numerical study detailing the early-stage ignition mechanism following a Mach reflection of two incident shocks, 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
• DOI: 10.1016/j.proci.2025.105948
• EISSN: 1873-2704
• ISSN: 1540-7489
• Language: English
• Keywords: detonation wave; Mach reflection; numerical simulation; weakly-curved quasi-steady detonation