关键词: 航空发动机;综合换算率;混频;飞行剖面

Abstract: For the life control and management of some internal military aero engine in the service,based on the flight profile and task frequency mixing,the assessment process of comprehensive flight conversion ratio for aero-engine is established,and the assessment method for aero-engine conversion ratio is presented.Considering the effect of high temperature on the performance of material,the actual stress profile is converted to the stress profile at the same temperature.The rain flow counting method and the Good-man method and the Miner method for linear cumulative damage are all applied to estimate the flight mission conversion ratio of the active service military aero-engine which is applicable both to the compressor and the turbine.Considering the affecting factor such as the trial running for delivery at factory,the trial running under foot,the coefficient for the worst aero-engine and the decapitation factor,the flight mission conversion ratio of the active service military aero-engine is amended and the comprehensive flight conversion ratio of the active service military aero-engine is assessed.The comprehensive flight conversion ratio is applied into the life control and management of the active service military aero-engine.Result shows that the comprehensive flight conversion ratio is correct and reasonable,and is applicable for actual technical application.

Key words: Aircraft engine;Comprehensive flight conversion ratio;Task frequency mixing;Flight profile