Geometric and CFD analysis of a NACA 65 blade row for axial compressors

This report dives into a computational study of the aerodynamic behavior of a NACA 65- (12)10 blade profile. This particular profile is mostly used in axial compressors due to its lowloss characteristics. The main objective of the work is to recreate the profile geometry, generate a high-quality computational mesh, and perform CFD simulations to compare its performance under several angles of attack. The results obtained by the CFD simulations are then compared with historical experimental data obtained by the American agency NACA. The geometry was reconstructed by combining a cambered mean line model and a basic thickness distribution. Particular attention was then given to refining the leading edge and the trailing edge through Bezier curves to improve the smoothness of the profile and the mesh quality. In order to replicate test conditions, a fluid domain has been defined, following the selection of a solidity of 1 and an inlet flow angle of 45°. With the usage of the open source software Salome it was possible to create meshes with both fine and very-fine resolution, including viscous layers to resolve boundary layer effects. CFD simulations were performed in ANSYS Fluent assuming incompressible flow at a Reynolds number of approximately 250000 and using the SST k-ω turbulence model. Simulating the tests at six different angles of attack led to developing a detailed analysis of lift and drag behaviour in the airfoil, and consequently to evaluate the conditions of maximum aerodynamic efficiency. Overall, the results proved to be satisfactory in terms of the trend, which is consistent with the experimental data. However, some discrepancies were observed near stall conditions and in absolute efficiency values. From a methodological point of view, this study highlights both the strengths and the limitations of CFD simulations for aerodynamic design. Indeed, this method is very effective if accompanied by experimental validation and test campaigns. The work, therefore, offers wide margins for future improvements, such as refining turbulence model, introducing 3D effects, and optimizing the blade geometry to increase performance.