Propagation of Out Warding Flame for Combustible Gas in Cylindrical Confinement

摘要

In the paper outward propagation of cylindrical flame in confinement geometry is investigated by high-resolution simulations. It is first found that globally cylindrical flame acceleration contains three stages: exponential self-acceleration, linear acceleration, and ultrafast acceleration. The numerical results show that linear acceleration is as result of gas compressibility, coupling positive-feedback mechanism. With formation of turbulent flame, gradient mechanism is observed, while transition to detonation does not occur.