Analysis of forced response for bladed discs mistuned by material anisotropy orientation scatters

A new method is developed for the forced response analysis of mistuned bladed discs manufactured from anisotropic materials and mistuned by different orientations of material anisotropy axes. The method uses: (i) sector finite element (FE) models of anisotropic bladed discs and (ii) finite element models of single blades and allows the calculation of displacements and stresses in a mistuned assembly. A high-fidelity reduction approach is proposed which ensures high accuracy modelling by introducing an enhanced reduction basis. The reduction basis includes the modal properties of specially selected blades and bladed discs. The technique for the choice of the reduction basis has been developed, which provides the required accuracy while keeping the computation expense acceptable. An approach for effective modelling of anisotropy-mistuned bladed disc without a need to create a finite element model for each mistuning pattern is developed. The approach is aimed at fast statistical analysis based on Monte-Carlo simulations. All components of the methodology for anisotropy-mistuned bladed discs is demonstrated on the analysis of models of practical bladed discs. Effects of anisotropy mistuning on forced response levels are explored.