Hydrodynamic aspects of end-gas autoignition

Within the small-Mach-number approximation, employing an appropriate scale-separation procedure, a reduced zero-dimensional model for deflagrative combustion occurring in a closed vessel is formulated and analyzed. It is shown that progressive compression of the unburned gas (end-gas) induced by the burned gas thermal expansion may result in end-gas autoignition, provided the vessel is large enough. A theoretical interpretation is given to the effect of the flame velocity reversal occurring prior to the autoignition event.