基于区间不确定性的涡轮盘强度可靠性优化设计

Reliability Optimization Design for Turbine Disk Strength Based on Interval Uncertainty

关键词:  涡轮盘  有限元分析  区间不确定性  响应面法  可靠性优化设计 

Key words:  Turbine disk  Finite element analysis  Interval uncertainty  Response surface method  Reliability optimization design

摘要:

针对涡轮盘在初期设计过程中可利用试验数据少的问题,采用区间模型描述不确定性,以非概率可靠性模型描述可靠性,提出了基于区间不确定性的涡轮盘强度可靠性优化设计方法。同时,为了提高该方法的计算效率,提出两级分阶段构造法,建立非概率可靠性指标关于设计变量的响应面函数,并以此响应面函数表征可靠性约束,从而将可靠性优化设计的双重优化过程转化为单重优化过程,简化了算法结构。典型涡轮盘强度可靠性优化设计算例结果表明,所提方法降低了对试验数据量的需求,且计算成本较低,计算效果较好,能够较好适用于涡轮盘的初期设计。 

Abstract:

Aiming at the problem that the experimental data is lack in the initial design stage of the turbine disk, the reliability optimization design method for turbine disk strength based on interval uncertainty was developed, in which the uncertainty and reliability were represented with interval model and non-probabilistic reliability model, respectively. Moreover, to improve the computational efficiency of this method, the reliability restriction is characterized by the response surface function of the non-probabilistic reliability index through two-level phased formulation, which converts the double loop structure of the reliability optimization into the single loop structure, and therefore simplifies the algorithm structure. At last, the reliability optimization design for typical turbine disk strength was applied as the numerical example. The results show that the method presented can reduce the demand of the experimental data.In addition it has lower computational cost and good computational effect.This method is adaptive to the initial design of the turbine disk.