NH₃/DME oxidation and kinetic interaction up to 100 atm

Blending ammonia (NH₃) with oxygenated fuels is promising to promote NH₃ application in internal combustion engines. In this work, NH₃ and DME dual fuel oxidation and kinetic coupling are experimentally studied by using a supercritical pressure jet-stirred reactor (SP-JSR) at 100 atm, over a temperature range of 500-850 K, and at fuel-lean condition. The experimental results show that the addition of DME to NH₃ promotes the low-temperature reactivity of NH₃ due to the strong low-temperature reactivity of DME. Numerical results using HP mech show that the addition of NH₃ to DME inhibits DME oxidation at low-temperature region while promotes DME oxidation at intermediate temperature region. NOx kinetics brought by NH₃ oxidation is the main reason to promote DME oxidation at intermediate temperature region. Reaction NO+HO₂=NO2+OH (R1) converting HO₂ to OH directly enriches the radical pool. Meanwhile, NH2+NO2=H2NO+NO plays an important role in converting NO₂ back to NO to promote R1 and promoting NH₂ consumption.