Shock tube measurements and model development for morpholine pyrolysis and oxidation at high pressures

Fuel decomposition time-history measurements during morpholine pyrolysis and ignition delay time measurements during morpholine oxidation were carried out behind reflected shock waves in a high-pressure shock tube. For the pyrolysis studies, morpholine concentrations of 5000 ppm in argon were employed, with experiments covering the temperature range 1086–1404 K and pressure range 20–23.6 atm. For the ignition delay time measurements, experiments covered the temperature range 866–1197 K with pressures near 15 and 25 atm, oxygen mole fractions of 4% and 21%, and equivalence ratios of 0.5, 1, and 2. A morpholine reaction set developed to simulate low-pressure flames was updated based on the current shock tube data, recently published rate constants for relevant reactions, and newly calculated thermochemistry. The simulations from the updated set were in good agreement with the current shock tube experiments.