降低冒烟数燃烧室火焰筒头部改进设计研究

To solve the problem of relatively large smoke number for an aero-engine combustor, the determination of the soot formation mainly occurring in the flame tube dome during the stage of primary reaction is made by analysis of the processes for combustion chemical reaction of the aviation kerosene and oil-air mixing combustion in combustor. The improvement measure is proposed to replace the single-stage swirler of the flame tube dome with the swirler cup and adjust its structural parameters. The comparative analysis is carried out for the performance of the flame tube before and after its improvement through the numerical simulation and the sector test. The research results show that the flow field of combustor dome is changed from single vortex to double vortexes and the fuel distribution is more uniform by application of the swirler cup compared with the single-stage swirler. The degree of the local fuel-rich is reduced in the high temperature of the dome, thus the soot formation is decreased. Through the design improvement, the smoke number of combustor is reduced largely, the total pressure recovery coefficient doesn t have great change and the lean flameout oil-air ratio reaches 0. 004 6. It can still satisfy the requirements for the engine opeation.