用Excel进行威布尔型产品可靠性数值仿真评估

Reliability Numerical Simulation Estimate for Product with a Weibull Failure Distribution by Excel

基于最小二乘法,利用Excel的已有函数和单元格的引用,估计威布尔分布的参数m和η,用RAND()函数产生的随机数和逆变法抽取服从分布参数为m和η的威布尔分布抽样样本,计算可靠度的一个抽样值,反复抽样,得到可靠度的分布密度函数,用SMALL()函数返回可靠度置信下限的仿真值。实例表明,仿真结果与计算结果很接近,用Excel进行可靠性数字仿真,可以避免繁杂的编程工作,方便实用。

The existing functions and cell citation of Excel were used to estimate the parameter m and η of Weibull distribution based on least squares method. The random sample fitted Weibull distribution with parameter m and η was acquired with the random number produced by RAND 0 and the inverter method, and the sampling value of reliability was computed. By repeating the sampling in this way, the probability density function of reliability was obtained, and the lower confidence limit of reliability was obtained by SMALL 0 From the practical example, it is shown that the simulation result is very close to the computed value, and the reliability numerical simulation using Excel is convenient and practical by avoiding complex programming work.