Abstract:
We investigated the deflagration-to-detonation process in hydrogen-air mixtures, a field extensively studied due to the energy-wise advantages of the detonation fuel cycle over conventional fuel cycles. Hydrogen's potential as a fuel has made the development of hydrogen detonation engines a highly relevant research problem. In lab experiments, deflagration typically initiates due to increases in energy and temperature, often triggered by successive electric discharges or interactions with obstacles in channels. Many studies have simulated the behavior of reacting gas flows in channels with obstacles or the initiation of deflagration via hot spots as analogs to electric discharges.In this study, we modified an algorithm originally introduced by the author to calculate the initiation of deflagration in hydrogen-air mixtures. The modification involved implementing a strict counterflow version of the Chakravarthy-Osher difference scheme, which reduced oscillations in the mixture component concentrations. Using this modified algorithm, we simulated the initiation of deflagration of hydrogen-air mixtures in channels with obstacles.For the simulation of the kinetic processes, we employed two algorithms to solve the system of kinetic equations. The first algorithm solves the full system of kinetic equations, while the second is based on the branching chain reaction theory proposed by N. Semenov. The results of these simulations demonstrate the reliability of the branching chain reaction algorithm for the simulation of deflagration in hydrogen-air mixtures, aligning well with the results obtained for the full multistage kinetic system.
Keywords:deflagration-to-detonation period, deflagration-to-detonation transition, system of stiff differential equations, branching chain reactions.
Fulltext:
PDF file (256 kB)