NH3/H2/DME三元燃料层流预混火焰特性的化学动力学研究

As a new type of energy carrier and clean zero-carbon fuel, the application of ammonia is strategic significance for achieving carbon neutrality in power plants. However, ammonia combustion has the disadvantages of low flame stability, low reactivity, high auto-ignition temperature and high NOx emission.For the above problems, a relevant study is carried out to characterize the combustion of ternary fuel laminar premixed flame basis for H2/DME fueled ammonia combustion based on chemical kinetics.The chemical reaction mechanism of NH3/H2/DME ternary fuel was constructed and verified, and the mechanism of the influence of H2/DME blending on the laminar flame characteristics of ammonia-fueled composite combustion at ambient temperature and pressure was investigated.The results show that H2 focuses on increasing the OH concentration at the flame front of the composite combustion, while DME focuses on increasing the CH2O concentration at the inner flame front, both can improve the flame stability.H2 can shorten the ignition delay time of the composite combustion process and DME can reduce the autoignition temperature of the composite combustion, so the ternary fuel of NH3/H2/DME can realize the comprehensive improvement of the laminar flame stability, ignition delay time (IDT)and auto-ignition temperature of the composite combustion of ammonia.In addition, the key to suppressing NOx generation during ammonia composite combustion is found to be the regulation of the concentration and reaction direction of NH and HNO in combination with reaction flow analysis.