Numerical Analysis of Sand-Induced Erosion in a Transonic Axial Compressor Rotor Under Varying Particle Sizes

During operation in sand-laden environments, aero-engine compressor blades suffer severe localized erosion, leading to progressive degradation of compressor stage performance over the engine service life. This issue is particularly critical for high-speed transonic compressor rotors. In this study, the erosion behavior of a transonic axial-flow compressor rotor is investigated using a CFD-based erosion prediction framework. Five representative particle diameters are selected based on the particle size distribution measured at the outlet of the upstream inlet duct. Three engineering-relevant particle mass loadings are prescribed through an accelerated loading approach. Under identical operating conditions, blade erosion patterns and surface aerodynamic responses are compared between clean and sand-laden inflow cases. The results show that the erosion level on the suction surface is approximately one order of magnitude lower than that on the pressure surface, and the suction-surface erosion appears as scattered spot-like patches. Within the considered loading range, smaller particles produce lower erosion-rate densities but cause stronger flow-field disturbances, whereas larger particles show the opposite behavior. As particle concentration increases, the contribution of particles to the radial variation of leading-edge erosion rate density increases by several times. Large particles mainly promote localized material removal and blade geometric degradation. Overall, these findings clarify the erosion–aerodynamic coupling characteristics of a transonic compressor rotor under different particle sizes and concentrations, and provide practical guidance for compressor design and protection in sand-laden environments.