Combustion Products Analysis of Large-scale Kerosene/air Rotating Detonation Combustor

Large-scale rotating detonation experiments with a 500 mm outer diameter combustor are carried out in this study. The experiment used aviation kerosene (RP-3) as fuel and hot air as oxidant. Detonation is successfully initiated between the equivalent ratio of 0.85 and 1.20. The engine works steadily for 2 s and 3 s. The detonation wave modes are two-wave collision. The average speed of detonation wave is between 920 m/s and 980 m/s. The detonation wave velocity increases with the increase in equivalence ratio, and when the equivalence ratio exceeds 1.0, the increasing trend of detonation wave slows down. Through sampling and analysis of detonation gas, it is found that the uneven distribution of fuel supply pressure in large-scale rotating detonation experiment results in inconsistent local equivalent ratio and uneven combustion. The complete combustion rate based on carbon atoms is used to evaluate the combustion completeness of detonation. With the increase in equivalent ratio, the combustion changes from deflagration to detonation, and the detonation combustion completeness gets better. The combustion completeness of detonation wave is the best near the appropriate chemical equivalent ratio. Once the equivalent ratio exceeds 1.0, then oil-rich combustion occurs and the strength of the detonation wave becomes weaker.