基于正态容许限法的点火器可靠性评估

Reliability Evaluation of Igniter Based on Normal Allowable Limit Method

点火器是运载火箭动力系统的重要组成部分。为了解决其高可靠性的评估问题,提出一种基于正态容许限法的点火器可靠性评估方法。首先选择点火冲量和压力峰值作为点火器输出敏感性能参数,然后提出采用W检验法对点火冲量和压力峰值数据进行正态分布检验,最后基于正态容许限系数给出了点火器点火可靠度和结构可靠度的点估计和区间估计。采用该方法对某点火器进行了可靠性评估,评估结果为该点火器点火可靠度和结构可靠度点估计约为0.999999,置信水平0.95下,点火可靠度下限为0.999998和结构可靠度下限为0.999999,表明该点火器具有较高的可靠性水平,达到了置信度为0.95,可靠度下限为0.9999的要求。本方法可为其他结构、功能相似的点火器高可靠性评估提供借鉴。

The igniter is an important part of launch vehicle power system.In order to solve the problem of high reliability evaluation,a reliability evaluation method of igniter based on Normal Allowable Limit Method is proposed.First,the ignition impulse and pressure peak are selected as the igniter output sensitive performance parameters,and then the W test method is proposed to test the normal distribution of the ignition impulse and pressure peak data.Finally,the ignition reliability and structure reliability of the igniter are given based on the normal allowable limit coefficient.This method is used to evaluate the reliability of an igniter.The evaluation result is that the ignition reliability and structure reliability of the igniter are estimated to be about 0.999999,with a confidence level of 0.95,the lower limit of ignition reliability is 0.999998 and the lower limit of structure reliability is 0.999999,which shows that the igniter has a high level of reliability,reaching the requirement of a lower limit of reliability of 0.9999 with a confidence level of 0.95.This method can provide reference for high reliability evaluation of other igniters with similar structure and function.