Momentum loss as a mechanism for deflagration-to-detonation transition

A reduced model for premixed gas filtration combustion where the nonlinear effects are discarded everywhere but in the reaction rate term and where the only accounted for effect of the porous medium is its resistance to the gas flow is explored. While ruling out formation of shock waves the model appears rich enough to cover detonation-like phenomenon with barodiffusion acting as a driving agency. It is shown that depending on the initial conditions this creeping detonation mode is evoked either immediately or emerges after some time delay as a product of an abrupt transition from the low-velocity deflagration. The transition is triggered by a localized thermal explosion in the extended (friction-induced) preheat zone gradually formed ahead of the advancing deflagration.