Browse Articles
Discover research articles across all indexed journals
Dynamic adjustment strategy of sensor nodes based on artificial fish swarm algorithm
Research on forward-looking sonar target detection algorithm based on edge enhancement and multi-scale feature fusion
US politicians push agencies to restrict research collaboration with China
Higher insulin resistance is associated with gastrointestinal polyps in women and older adults
‘Explosive diarrhoea’ outbreak grips US: how researchers are hunting its source
Programming Reaction-Network Bifurcations for Selective Amino Acid Electrosynthesis
Edge optimized hybrid quantum-classical ensemble framework for EEG and MRI based epileptic seizure detection in IoMT
Unveiling the structural, electronic, optical, and transport properties of Cs₂SeCl₆ double perovskite for clean energy
A global capital for AI safety is emerging — and it’s not in Silicon Valley
Machine learning-based electrofacies characterization of the Asmari reservoir in the Ahvaz oil field (SW Iran) using multi-resolution graph-based clustering (MRGC) and hydraulic flow unit (HFU) analysis
Why do astronauts’ bodies waste away? Space-station study points to mitochondria
Cold atmospheric plasma accelerates wound closure and reduces pathogenic bacterial load in diabetic foot ulcers: a randomized controlled trial
CRISPR gets a power boost from AI-designed ‘molecular scissors’
State media control influences large language models
Photocatalytic Denitrative Homo- and Cross-Coupling of Nitroalkanes toward the Synthesis of Alkenes
Effects of chamber geometry and ignition sequence on high-pressure pre-mixed H2/O2 flame propagation and deflagration-to-detonation transition
Abstract Numerical simulations were performed to investigate the effects of chamber geometry and ignition sequence on pre-mixed H 2 /O 2 flame propagation and deflagration-to-detonation transition (DDT) under high-pressure conditions. Based on the OpenFOAM platform and utilizing a detailed H 2 /O 2 chemical kinetic mechanism consisting of 8 species and 19 elementary reactions, high-resolution simulations were conducted on flame development in two-dimensional axially symmetric combustion chambers. By altering geometric parameters such as chamber length and contraction angle, as well as implementing different multi-point ignition sequences, the study analyzed flame acceleration mechanisms, turbulent evolution patterns, and DDT (deflagration-to-detonation transition) triggering mechanisms. The results show that chamber contraction geometry modifies flame development by changing the available propagation space and reflected-shock trajectories. In the elongated contraction channel, the rightward-propagating flame is stretched into a finger-like structure and accelerates to approximately 1000 m/s before DDT initiation. The ignition sequence determines the shock-wave interference pattern; later-ignited flames experience pronounced deflection and compression due to pre-existing shock waves. Two dominant DDT triggering mechanisms are identified: hotspot-induced DDT caused by reflected-shock focusing and flame-stagnation-induced DDT caused by sustained shock–flame coupling in confined regions. Ultimately, detonation wave evolution is governed by both high acoustic impedance ratios and intense interface instability. This study clarifies the roles of contraction geometry and ignition sequence in controlling flame–shock coupling and DDT initiation in confined high-pressure hydrogen–oxygen combustion systems.