氨掺混丙烷氧化和氮氧化物排放实验及动力学机理

In order to investigate the chemical kinetic insight of ammonia with active promoters on combustion control and NO_x formation/emission, firstly, experiment of ammonia blended with propane oxidation was conducted in a jet-stirred reactor. Mole fractions of intermediates were measured at 800−1 250 K and the equivalence ratio of 0.5, 1.0 and 2.0. Secondly, based on error function analysis, NUIG-ZHANG model was established. Finally, kinetic analysis of ammonia oxidation and NO formation was conducted based on experimental data and NUIG-ZHANG model. The results show that NUIG-Zhang model provides accurate prediction on experimental data. HCO, C₂H₅, and IC₃H₇ are produced through propane oxidation, which further trigger the OH and HO₂ formation. This pathway boosts the consumption of ammonia. Mole fraction of NO does not change monotonically with temperature, which increases firstly and then decreases, and increases finally. In the temperature range of 900 K to 1 050 K, the branching ratio of NO formation reactions increases firstly and then decreases. The branching ratio of NO reduction reactions decreases firstly and then increases. Therefore, NO concentration increases firstly, and then decreases. At temperature of above 1 100 K, the mole fractions of active radicals involved in key reactions increase, such as NH₂, NH, HNO, H, OH and O. Thus, the mole fraction of NO increases with the increase of temperature.