NOx Emissions from Jet A-air Detonations
Karthikeyan M. Iyer, Ajay V. Singh
Abstract
View Video Presentation: https://doi.org/10.2514/6.2021-3679.vid The propulsive application of detonation-based engines has been well recognized since detonations offer an environment for efficient burning of a given fuel-oxidizer mixture with increased efficiency. The use of liquid hydrocarbon fuels is necessary for these advanced detonation-based combustors to resolve problems associated with the fuel payload and operating cost. However, using jet fuels for such combustors is a challenging task since the propagation limits and stability of detonation waves in such scenarios are not known and warrants further investigation. Also, NOx emissions from such systems have so far received less attention. Since the emissions control protocol has become more stringent for air-breathing engines, it is necessary to understand the NOx chemistry of real distillate fuels in a detonating environment. For the mixtures and operating conditions featuring promising detonability, NOx formation in the detonation wave has been simulated using a detailed HyChem Jet-A reaction model combined with the NOx model of Glarborg et al. The purpose of the present study is to quantify the effect of initial temperature and initial pressure on NOx emissions for JetA-air detonations over a wide range of initial conditions. The effect of dilution on NOx emissions was also investigated in the presence of inert diluents like argon and helium. The observation from the computed results indicates that the addition of inert diluents significantly reduces the NOx emissions, with the comparative difference in NOx suppressing ability between argon and helium being insignificant. The present study lays the groundwork for the optimized operation of liquid hydrocarbon-fuelled detonation-based engines and enables an insight into the potential measures that can be employed for reduced NOx emissions in such devices.