Influence of contaminations on combustion kinetics in hydrogen-fueled engine

In this work, we investigate the combustion of hydrogen fuel through the wind tunnel tests. Two kinds of fuel, the pure hydrogen and the hydrogen-ethene mixture, have been chosen to heat the oxygen-enriched air. It is found that the stable pressure in the engine combustor and the thrusts is almost the same in two cases. A valuable feature we revealed is that the heating pattern of hydrogen and ethene mixture leads to a considerable delay of the establishment of the wall pressure in the combustor, compared with the pure hydrogen case. This phenomenon implies a longer ignition delay time for the mixture case. The shorter ignition delay resulting from the hydrogen heater is attributed to the continuity of chain propagation and the exclusion of the less active C-containing radicals.