Numerical Simulation of Deflagration to Detonation Transition of Two-phase Detonation Wave

Mechanism of Deflagration to Detonation Transition (DDT) of liquid octane/air mixture is studied by using the theory of one-dimension reaction flow, particle-trajectory model and two-step reaction model, of which the numerical formulation is described on the Sγα,β scheme ofgasdynamicstep and a second-order accurate Adams method ofchemicalstep in Lagrangian mass coordination system, based on which code-CPTD is developed. The paper investigates numerically the generation, evolution, propagation and basic properties of liquid-fueled detonation structure. Simulations reveal that due to latent heat of vaporization required and drag force of fuel droplets the characteristic parameters of two phase detonation wave, such as peak pressure and propagation velocity are below theoretical values. It's found that the numerical results are in good agreement with experimental ones, which shows that a feasible numerical method has been provided here to simulate pulse detonation engine operation processes including DDT phenomena.