| As a part of the NSFC project "enhancement mechanism of focusing shock-flame interactions on deflagration-to-detonation transition", the theoretical analysis, numerical simulations and experimental validations are carried out to study the flame instabilities induced by shock-flame interactions.Some theory research about shock-flame interaction stability is discussed. Some research about the generation and development of vorticity and the distortion of edge of light gas ball is done. The Richtmyer-Meshkov instability is analyzed. The Kelvin-Helmholtz instability induced by small disturb in the two unmixed fluid interface is discussed by means of the established mathematical model. And five phases of instabilities development are introduced, especially, the nonlinearity process of the instabilities is analyzed.A numerical model, in terms of two-dimensional multi-component axisymmetric Euler equations coupled with a chemical reaction source term, was constructed. A splitting-operator technology was used to solve the equations. The gas dynamic equations were solved by using the second-order wave propagation method, and the chemical reaction source term of methane-air is solved by using a chemical kinetic mechanism including 19-element reactions and 14 species.Based upon methods constructed above, the interactions between the incident shock wave and flame bubble, and between the reflected shock wave and distorted flame for CHVair mixture were investigated numerically. The evolution and properties of flame instability induced by incident and reflected shock waves were discussed in according to computational results. The computational results were compared with the experimental results, in order to validate the effectiveness of the numerical simulation.
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