Study On The Reliability Analysis And Assessment Method Of The Aerospace Pyrotechnic Devices

In this paper, the reliability analysis and assessment method of the aerospacepyrotechnic devices is studied. Taking the aerospace pyrotechnics devices as anexample, the ignition reliability and output performance reliability under the hightemperature conditions were analyzed and evaluated. The evaluation result of thesystem reliability was given.First of all, the SIMULINK simulation software was employed to simulate theoutput performance of single igniter and double igniter, and the relationship betweenoutput pressure and time within different structures was analyzed. The numericalsimulation study on shell stress distribution within the different structures wassimulated by the Autodyn finite element simulation software. The reference for thedesign of tooling and test plan was provided.Furthermore, the ignition reliability of the pyrotechnic device under hightemperature conditions were tested and evaluated by Neyer D-Optimal Method. Theresult of parameter estimation under the condition of Logistic distribution wasconcluded. According to experimental data the evaluation results were given. Thenthe product’s output performance and reliability under high temperature and normaltemperature were tested and evaluated respectively. The output reliability underdifferent conditions was analyzed. The evaluation results of output reliability wereconcluded through different methods.Last, the system reliability of the product was evaluated by Bayes theory. For thedetermination methods of inherited factor in the mixed prior distribution, the theory ofcombination of qualitative and quantitative to determine the inherited factor wasproposed. The similarity criterion was given when used qualitative method todetermine the inherited factor. Two typical quantitative methods of goodness of fit andKullback information to determine inherited factors were analyzed through numericalsimulation. The applicable conditions of the two methods were concluded. Finally，based on the system reliability evaluation methods proposed in this paper, thereliability of the aerospace pyrotechnics devices was valuated. It could be used as areference for the reliability evaluation of similar products.