Ignition of acetylene by high-voltage nanosecond discharge

The ignition of acetylene by low-temperature nonequilibrium plasma of a high-voltage nanosecond discharge is experimentally and theoretically studied. The ignition delay time for С$_2$Н$_2$ : О$_2$ mixtures behind the reflected shock-wave front is measured. It is experimentally shown that discharge initiation leads to a considerable shortening of the ignition delay time. For lean mixtures, this effect is more pronounced. Numerical modeling of discharge and ignition processes under the experimental conditions is carried out. A good agreement between the calculation and experimental results for the ignition delay time is obtained. Analysis of the calculation results shows that the dominant mechanism of the effect of nonequilibrium plasma on ignition is related to the accumulation of atoms and radicals in discharge plasma.