Study of the detonation wave in a rotating detonation combustor using hydrogen and mixtures ethylene-acetylene

Abstract

In this study, a comparison between the use of hydrogen and a mixture of ethylene-hydrogen-acetylene as fuels is made in order to evaluate the characteristics of the detonation wave in a rotating detonation combustor. For the experimental development, an annular combustor, which has been connected to a supply of air, fuel, and hydrogen, has been used. The air and the type of fuel have been injected separately into the combustion chamber. The measurement of key parameters involves the use of ionization probes and pressure sensors, which have been located in the body of the combustion chamber. The results obtained indicate that hydrogen can reach an average pressure in the detonation wave 37% higher compared to the fuel mixture (ethylene-hydrogen-acetylene). For hydrogen, the equivalency ratio range is 38% higher compared to the fuel mixture. Therefore, the use of fuel mixtures is in a more limited operating range. The study of the detonation wave velocity indicates that the mixture of fuel and hydrogen can reach 68% and 93% of its ideal wave detonation velocity. However, in terms of height, both types of fuels reach a wave height of 30 mm. In general, hydrogen has characteristics that are more favourable in its detonation wave.