URANS Simulations of Deposition in a Rotor Passage of the First-Stage Turbine for an Aero-Engine

Abstract

Atmospheric particulate pollutants in high-temperature and high-speed gas are prone to deposit in aero-engine turbines. The deposition changes the blade profile, resulting in a degradation of aerodynamic performance, increases surface roughness and blocks film cooling holes and internal cooling channels, thus reducing the cooling performance of the blade. Therefore, the blades are easily ablated, especially for the rotating parts as they have high rotating speed. In present study, unsteady numerical simulations were performed to investigate the effects of particle deposition by studying the movement patterns and deposits distributions of particles in the rotor passages. The effects of rotating speed, tip clearance, and cavity depth on the movement and deposition of contaminant particles were illustrated. Results show that the deposition on the blade surfaces varies with the rotating speeds and the rotor tip clearances. The deposits are mainly concentrated on the pressure side of the blade where multiple rebounds of the particles are observed under a cruise operating condition. More particles flow into the tip clearance carried by the stronger leakage flow resulted from a larger tip clearance, and the squealer tip increases the capture efficiency of the particles on the blade tip.