涡轮叶片的网格参数化方法及其寿命可靠性优化

A mesh parameterization method and life reliability-based optimization for turbine blade

涡轮叶片的寿命可靠性优化对保障发动机安全,提高发动机使用寿命具有重要意义。传统的确定性优化由于没有考虑不确定性因素的影响,其结果往往导致结构可靠性低,严重威胁发动机的安全。针对复杂的含气膜孔几何变量的涡轮叶片几何构型,提出局部参数化网格变形方法,在关注的叶片前缘部分采用六面体网格,并利用局部网格变形法实现其参数化变形,其他部分采用四面体网格,以缩短其网格划分时间,提高其网格划分效率。所提方法实现了不确定条件下的含气膜孔几何变量涡轮叶片的寿命可靠性优化,在满足可靠性约束和几何约束的条件下,使得涡轮叶片基于不确定性的寿命均值提高了18.36%。

The optimization of the life reliability of turbine blades is of great significance for the safety and service life improvement of aeroengines.The traditional deterministic optimization method does not consider the influence of uncertain factors,which tends to cause low structural reliability,seriously threatening the safety of the aeroengine.Thus,this paper focuses on the life reliability-based optimization of the turbine blade in uncertain environments.A local mesh deformation method is proposed for the turbine blade with geometric variables of the film hole to realize mesh parameterization.Based on the proposed method,the life reliability-based optimization of the turbine blade with film hole geometric variables is achieved under uncertain conditions.With satisfying reliability constraints and geometric constraints,the average lifetime value of turbine blades based on uncertainty is increased by 18.36%.