Reduced detonation kinetics and detonation structure in one- and multi-fuel gaseous mixtures

摘要

Two-step approximate models of chemical kinetics of detonation combustion of (i) one-fuel (CH_4/air) and (ii) multi-fuel gaseous mixtures (CH_4/H_2/air and CH_4/CO/air) are developed for the first time. The models for multi-fuel mixtures are proposed for the first time. Owing to the simplicity and high accuracy, the models can be used in multi-dimensional numerical calculations of detonation waves in corresponding gaseous mixtures. The models are in consistent with the second law of thermodynamics and Le Chatelier's principle. Constants of the models have a clear physical meaning. Advantages of the kinetic model for detonation combustion of methane has been demonstrated via numerical calculations of a two-dimensional structure of the detonation wave in a stoichiometric and fuel-rich methane-air mixtures and stoichiometric methane-oxygen mixture. The dominant size of the detonation cell, determines in calculations, is in good agreement with all known experimental data.