The investigation for reconstructing the surface morphology of turbine blades and analyzing the deposition and flow field unsteady evolution

When aircraft engines operate in dusty environments, solid particles inhaled can deposit on the surface of turbine blades, leading to aerodynamic performance degradation, decreased cooling efficiency, and thermal corrosion damage, seriously threatening the reliability and lifespan of the engine. This study focuses on the explicit characterization of the morphology probability coupling effect in numerical simulations, and independently developed a User-Defined Function (UDF) program based on local relative height dynamic probability correction. Based on the Euler Lagrange multiphase flow calculation method and the sedimentation model coupled with dynamic grid technology, the numerical solution of sand deposition on the blade surface was carried out. The deposition characteristics of the blade surface under different inflow conditions were systematically studied, and the dynamic coupling mechanism of impact deposition and shear stripping was investigated. The particle size had a non-monotonic effect on deposition through the competition mechanism between flowability and secondary impact, while the incident angle of attack dominated the impact distribution shape by regulating the position of the stagnation point of the airflow. The flow velocity at different exit Mach numbers changes the trailing edge shear environment to control the peel strength. The final distribution of deposition was the result of the dynamic coupling of impact deposition and shear stripping, and the synergistic effect of multiple factors. Total pressure loss first remains stable and then increases exponentially, reaching up to an 8.9% rise at Ma=0.78. Deposition changes the wall morphology and induces small vortex systems and widening the wake, ultimately leading to a significant increase in total pressure loss at the blade outlet.