基于名义极限因子和降维方法的涡轮盘结构可靠性优化

结合名义极限因子方法完全实现了可靠性分析与优化过程的解耦,使可靠性分析成为进行优化之前的预分析过程,而在预分析中采用的基于降维的可靠性分析技术,在一阶可靠度方法(FORM)获得的计算结果的基础上进行适晕的数值计算就能够提高可靠性分析的结果.最后,以某涡轮盘结构优化为例对提出的方法可行性和效率进行了验证,结果表明:该方法...

Nominal limit state factor and dimension reduction method in reliability optimization for turbine disk

Computing intensity and cost consuming are two important difficulties in reliability-based design optimization (RBDO).the single-looping optimization (SLO) methods and the double-looping optimization (DLO) methods cannot deal with them.Some based on the inverse most probable point (MPP) transforms the probabilistic constraints to deterministic constraints,but they cannot decouple the two procedures including reliability analysis and optimization,in additional,there are too large errors because of using the first order reliability methods(FORM) in the methods to be adaptive in aero-engine design.The nominal limit state factor method was proposed that can decouple the two procedures of reliability analysis and optimization and can make the reliability analysis become a pre-procedure before optimization.Moreover,the uni-variate dimension reduction method was used to obtain accurate probability of failure that only requires the results of FORM in previous reliability analysis.Finally,an example on structure optimization for turbine disk was given to illustrate that the proposed methods are more efficient than the DLP method and are close to the deterministic optimization in efficiency.