14th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
Aircraft operation in harsh environments is affected severely by solid particulate ingestion with a subsequent gas turbine engine performance degradation. The existing literature in the turbomachinery erosion focuses on the blade damage caused by the impact of specific minerals (mainly quartz). However, recent tests identify the existence of other minerals/erodent in aero-engines environment. Thus, the existing quartz-based models are insufficient to evaluate blade erosion in a complete way. This work highlights, for the first time, the sensitivity of the compressor blades’ performance to the effect of mineralogy. Herein, three-dimensional numerical simulations of various minerals’ ingestion on the axial compressor NASA Rotor 37 are carried out by using a commercial Computational Fluid Dynamics (CFD) software. A two-way coupling algorithm between the particle motion and air flow field is implemented in order to incorporate the impact of dispersed phase on the continuum. The effect of turbulent dispersion on particle trajectories is also considered by applying stochastic tracking. The particle rebound from the rotor blade surface is predicted by a novel model, which incorporates the mechanical properties (Young’s modulus, Poisson’s ratio, density, indentation hardness and the yield strength) of both the particle and the blade material, and the collision conditions (particle impact velocity, impact angle). This model allows for the calculation of the energy dissipation, due to their plastic deformation, for different combinations of minerals and blade wall materials. The NASA Rotor 37 aerodynamic performance is validated with numerical and experimental data obtained from the literature. The results reveal that the energy loss during the particle-blade surface interaction is strongly affected by the particle’s kinematic characteristics. It is also shown that both the blade erosion rate and the subsequent aerodynamic efficiency deterioration change significantly upon the impingement of different minerals with various sizes. The highest probability areas for erosion and particle breakage along the blade chord and span are identified as well.