Precision polishing of turbine blade gas film holes by three-phase foam cavitation jet

To address the challenge of polishing air-film holes in aero-engine turbine blades, this paper proposes a three-phase foam cavitation jet polishing technique. The method utilizes the synergistic effect of abrasive erosion and cavitation to polish and improve hole quality. Computational fluid dynamics simulations using ANSYS Fluent analyzed the influence of jet pressure, abrasive concentration, and standoff distance (SOD) on wall shear stress and cavitation volume fraction. Experiments were conducted to evaluate these parameters’ effects on material removal rate and surface roughness, leading to the identification of an optimal combination: 0.8 MPa jet pressure, 7% abrasive concentration, and 10 mm standoff distance. Under these conditions, the surface roughness (Ra) of the polished holes was reduced to 4.45 ± 0.23 μm. This work provides a new approach and parameter guidance for the efficient, high-quality polishing of turbine blade air-film holes.