| A great lot of researches focus on shock wave, flame, detonation and deflagration to detonation transition (DDT) since the PDE (pulse detonation engine)concept was presented. The numerical simulations and theoretical analysis were carried out to study the flame instabilities and detonation initiation induced by shock-flame interactions in this dissertation. Some research work have been done as follow:The details of numerical simulation were presented in this dissertation, which were governing equations, equation of states, elementary reaction model, coupling of flows and chemical reactions, difference scheme, treatment of temperature and so on. And, Euler equation, 9 species and 20 reactions and NND scheme were used.The simulation results on shock-flame interactions were presented intensively. The effects of shock-flame interactions was to distort the flame and increase the burning rate of the flame. When the incident shock reached the front of the flame, its speed reduced because of the resistance of the flame, when the incident shock was inside of the flame, it spread faster because of the energy released from the flame, and when the incident shock departed form the flame, the flame enhanced the strength of shock through new shocks generated by the flame. The turbulent flame created conditions in nearby unreacted material that lead to ignition centre, or"hot spot", which could then produce a detonation.It was easier to induce and increase flame instabilities, burning rate and detonation initiation when the the incident shock mach number was bigger. If the mixture's equivalence radio was 1, and it had more the diluted gas (N2) in the mixture, then the flame spread slowly, and it was difficult to initiate a detonation. The bigger diameter could lead to higher pressure and temperature of the detonation. Obstacles, through their interactions with shocks and flames, helped to create environments in which hot spot could develop to a detonation.
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