Fatigue Life Analysis of Polyimide Film in Afterburner Fuel Distributor
Aiming at the problem of premature failure of organic material polyimide film in the afterburner fuel distributor of a turbofan engine,the material parameters of polyimide film and the temperature and the fluctuation amplitude of the film during use were obtained on the basis of previous investigation.The finite element simulation model of polyimide film was established in ANSYS software to study the Mises stress distribution and weak area distribution of the film when the film fails in the form of fracture.Based on the fatigue life calculation theory of probabilistic fracture mechanics,the fatigue life cycle times and their variation rules of the film under different reliability were obtained.The results show that there is stress concentration in the film,and the stress con-centration and weak area of the film occur at the outer edge of the film clamping.The fatigue life cycle times of the film under dif-ferent reliability are calculated,and the fatigue life cycle times decrease with the increase of reliability.