Constrained reaction volume approach for studying chemical kinetics behind reflected shock waves

We report a constrained-reaction-volume strategy for conducting kinetics experiments behind reflected shock waves, achieved in the present work by staged filling in a shock tube. Using hydrogen–oxygen ignition experiments as an example, we demonstrate that this strategy eliminates the possibility of non-localized (remote) ignition in shock tubes. Furthermore, we show that this same strategy can also effectively eliminate or minimize pressure changes due to combustion heat release, thereby enabling quantitative modeling of the kinetics throughout the combustion event using a simple assumption of specified pressure and enthalpy. We measure temperature and OH radical time-histories during ethylene–oxygen combustion behind reflected shock waves in a constrained reaction volume and verify that the results can be accurately modeled using a detailed mechanism and a specified pressure and enthalpy constraint.