当量比及航空煤油组分含量变化对喷嘴表面结焦积炭影响

For the effects of nozzle coking on overall performance and safety of aircraft engines, the dynamic combustion experiments were carried out to investigate the effects of combustion condition and mass fraction of n-hexadecane and butylbenzene on nozzle coking deposition, while the equivalence ratio and fuel components variation being conducted as experiment factors. It shows that the amount of coking and carbon deposition on nozzle surface has different features with decrease of equivalence ratio, and combustion zone temperature and extent of entrainment and counterflow are the main factors on coking deposition amount. The influence of butylbenzene on nozzle coking deposition amount is 19% bigger than hexadecane under the same blending ratio, which is equal to 10% when mixed with RP-3. SEM (Scanning Electron Microscope) results show that fuel droplets and dissociative hydrocarbon form complicated and porous network structure, and it includes deposition and adsorption of short filamentous coking and amorphous coking. Thus, the amount of coking deposition on nozzle can be decreased under a proper extent of equivalence ratio and fuel components variation.