The expansion of reaction products and formation of secondary waves inside the tube during detonation in gas-film systems (Q1112674)

A numeric simulation is performed of the formation of secondary shock waves produced by detonation propagating through non-premixed heterogeneous systems where the fuel in the condensed phase forms a coating on the inner surface of a tube filled with a gaseous oxidizer. Behind the leading shock wave in such systems in the near-wall area, fuel vapors mix with oxidizer forming a detonation-prone zone. This zone is shaped as a circular cylinder near the tube surface. Outside the potential detonation zone, the detonation waves degenerate into secondary waves which, according to calculations, intensify and converge at the tube access, forming a gas cumulative jet; interacting with the leading shock wave, this jet can cause fractures of the wave front and lead to the formation of cellular or spin structures.