Influence of sand particles on blade erosion of a transonic fan rotor

In the real service environments, especially in the dusty and sandy district, continuous ingestion of solid particles results in surface roughness on the fan rotor blades of aero-engine. Such kind of long-term erosion changes the blade geometry and degrades the aerodynamic performance. The study investigates the erosion behavior of sand particles on a transonic fan rotor blade, NASA Rotor 67, under design speed using Euler-Lagrange approach with the Finnie erosion model. The effects of particle diameter, mass fraction, and operation conditions are studied. The results indicate that as particle diameter increases, the average erosion rate on the blade firstly increases, then decreases and subsequently increases again. Particle diameter also significantly alters the erosion distribution on the blade. The increase of mass fraction proportionally rises the erosion rate but approximately maintains the erosion distribution. At different operation conditions, the tip leakage flow and flow separation have significant impacts on the erosion in localized blade regions. But for the particles with large diameters, the erosion distributions under different operation conditions are similar because the particle trajectories are more likely dominated by centrifugal force.