摘要
在疲劳寿命名义应力法的基础上,提出一种新的区间名义应力法对含不确定参数的疲劳寿命问题进行研究,并给出疲劳寿命各参数的区间灵敏度分析。本文同时考虑了平均应力和应力幅的影响,将S-N曲线及修正公式应用于疲劳寿命的计算之中。为了解决不确定参数对疲劳寿命结果的影响,引入区间分析方法对其进行求解;并利用区间壳技术来修正疲劳寿命的区间结果,来降低区间的易扩张性,通过一系列理论推导给出疲劳寿命对于不确定参数的区间灵敏度分析。最后通过数值算例与传统的概率分析方法相比较,结果表明当不确定信息较少时,文中提出的区间名义应力法是一种有效的、合理的选择,同时所提出区间灵敏度分析方法能够大大地降低计算量,应用更加方便、有效。
Based on the nominal stress method of fatigue life,we advanced a new interval nominal stress method to research the fatigue life with uncertain parameters.And the interval sensitivity analysis of each parameter also was presented.In this paper,to account for the effect of mean stress and stress amplitude when the S-N curve is used for the fatigue analysis of materials,some common correction formulas were used to correct the fatigue curve.In the process of interval operations,interval hull technique was used to limit the growth of intervals of fatigue life.Through a series of academic deduction,the interval sensitivity analysis of uncertain parameters was presented.Numerical examples were used to demonstrate the presented interval nominal stress method which may be a valid and reasonable alternative when the available information on the uncertain parameters is limited in comparison with the probabilistic method.The results also show that the presented interval sensitivity analysis method can alleviate the computational burden and is effective and feasible.
出处
《飞机设计》
2012年第6期42-46,共5页
Aircraft Design
