Numerical simulation of detonation reignition in H$_2$-O$_2$ mixtures in area expansions

Time-dependent, two-dimensional, numerical simulations of a transmitted detonation show reignition occuring by one of two mechanisms. The first mechanism involves the collision of triple points as they expand along a decaying shock front. In the second mechanism ignition results from the coalescence of a number of small, relatively high pressure regions left over from the decay of weakened transverse waves. The simulations were performed using an improved chemical kinetic model for stoichiometric H -O mixtures. The initial conditions were a propagating, two-dimensional detonation resolved enough to show transverse wave structure. The calculations provide clarification of the reignition mechanism seen in previous H -O -Ar simulations, and again demonstrate that the transverse wave structure of the detonation front is critical to the reignition process.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41914/1/193-10-1-33_00100033.pd