【摘要】 针对航空燃料燃烧时会在航空发动机喷嘴处产生大量结焦积碳,影响航空飞行器的飞行安全和使用寿命这一问题,研究了某型航空发动机喷嘴零部件上结焦积碳的生成情况.采用扫描电镜(SEM,Scanning Electron Microscope)、透射电镜(TEM,Transmission Electron Microscopy)、能谱仪(EDS,Energy Disperse Spectroscopy)以及X射线衍射技术(XRD,X-rayDiffraction)对结焦积碳的微观形态和性质进行了分析.结果表明:喷嘴零部件上生成的结焦积碳主要有两种形态:一种是丝状焦,另一种是颗粒状焦.其中,丝状焦只出现在零部件表面较光滑的位置,包括短纤维丝状焦和不定形丝状焦,是由金属催化作用所形成的;其形成与喷嘴零部件的结构、材质及表面粗糙度有关.颗粒状焦则主要集中在活塞表面,包括颗粒团聚状焦和颗粒分散状焦,是由催化作用与燃料热裂解共同作用所形成的.更多还原

【Abstract】 In order to solve the problem of air safety and service lives of the aircrafts with a mass of coking,the properties and micro-morphologies of coking which generated on aircrafts engines’ nozzles when aircraft fuel combusted were researched.The properties of coking were characterized by the techniques of scanning electron microscopy(SEM),transmission electron microscopy(TEM),energy disperse spectroscopy(EDS) and X-ray diffraction(XRD).It is found that two coking morphologies are produced: one is filamentous coking,and the other is granular coking.On the one hand,the filamentous coking only appears on the smooth surface of machine parts which includes short fiber filamentous coking and amorphous filamentous coking.It is generated by metal catalysis reaction and its formation has close connection with machine parts’ structures,materials and surface.On the other hand,the granular coking,including aggregative granular coking and dispersive granular coking,mainly emerges on the surface of nozzles’ pistons and it is aroused by the interaction of catalytic reaction and thermal cracking.更多还原