Structural Reliability Analysis Of Aircraft Electronic Equipment

Due to the particularity of aircraft electronic equipment’s working environment, higher reliability than normal and long time running are inquired. Because of expenses and the experimental condition, it’s difficult to evaluate the structural reliability through a large number of flight experiments. Therefore, the structure reliability analyses and designs of aircraft electronic equipment are necessary. Reliability analysis of traditional aircraft electronic equipment is mainly focused on the circuit of electronic equipment, components and so on. However, the investigation about reliability of electronic equipment structure research is seldom. Therefore, in this research, structural reliability research of aircraft electronic equipment based on structural finite element method is carried out.This research is funded by the national defense basic scientific research project.Cooperating one research institute with university and working together, engineering problems about the structural reliability of aircraft electronic equipment are solved.In this study, chosen the computer of air data processing for a type of aircraft as an research object, the general method for aircraft electronic equipment structure reliability modeling and analysis based on finite element method was proposed. The main research contents are shown as follows:1. The structure of aircraft electronic equipment is complex, under the precondition of reasonable classification it is divided into four levels. According to the finite element equivalent modeling principles and under the precondition of reasonable simplification, all levels of the finite element models are established.2. Establishing main components’ parametric model of aircraft electronic equipment by ANSYS software as random variables, the size of the structure, material properties and load are parameterized definition.3. Connecting the strength failure with stiffness failure as failure modes, a series system is formed. The structural failure probability is calculated approximately considering thestrength and stiffness, and then the system reliability is evaluated.4. Under the probability design module of ANSYS software based on stochastic finite element Monte-Carlo method, the structural reliability analysis process of strength and stiffness of structural is described in large overload, random vibration, and temperature load conditions. The distribution of stress or strain and the structural failure probability are obtained, and then the reliability evaluation is presented.The results show that reliability analysis of computer box of air data processing and printed circuit board in three conditions validate the good consistency between simulation and experiment results, which indicate that the modeling and analysis method are reasonable and effective and then it can be further promoted.