A Methodology for a Coupled Structural - CFD Analysis of Compressor Rotor Blades Subjected to Ice Impact With Uncertain Impactor Parameters

Abstract A method for a coupled structural – Computational Fluid Dynamics (CFD) analysis of a compressor rotor blade subjected to an ice impact scenario is investigated to assess the impact related blade deformations from a structural and fluid-dynamics perspective. On the basis of a probabilistic approach, in total 50 impact scenarios are derived for this study. In a first step the numerical structural model based on Finite Elements (FE) is discussed, including several parameter variations like impact location, ice diameter, ice density and rotor speed. Different analysis steps are subsequently carried out using LS-DYNA implicit / explicit on a high performance computing (HPC) cluster. Resulting blade deformations are evaluated in terms of local plastic deformation, cup size and modal parameters in comparison to the undamaged reference structure. The resultant post-impact blade geometry is extracted from the result data and passed to the CFD simulation setup in a fully automated manner. Based on this deformed structural mesh data, the fluid mesh is morphed via a radial basis function (RBF) approach and analysed with CFD. Finally, an uncertainty quantification study is performed to assess the variability of results with regard to the definition of the ice impactor.