Biomimetic design and optimization of aero-engine blades inspired by humpback whale tubercles

Aiming at the performance optimization of turbine power simulator fan blades, this study introduces the bionic structure of humpback whale pectoral fin tubercles to modify the original blade airfoil designed by Changchun University of Science and Technology, so as to improve aerodynamic performance while analyzing structural strength. Python is used to program the forming of bionic blades with quadratic curve controlled by three control points. The static aerodynamic elastic characteristics are solved by finite element method, and the unsteady compressible N-S equations are numerically calculated by node-based finite volume method with S-A turbulence model and LU-SGS time discretization. The partitioned fluid-structure coupling strategy is adopted for iterative computation. The results showed that the ratio of the maximum deformation of the bionic blade to the diameter of the blade disk decreased from 0.306% to 0.239%, indicating that the strength of the bionic blade was theoretically slightly enhanced. The flow field was effectively optimized, with a 4.09% increase in single-channel flow rate, a 4.85% increase in pressure ratio, and an improvement in blade efficiency from 67.014% to 89.861%(optimize fan seal). The bionic structure suppresses flow separation and vortex dissipation, homogenizes the pressure, temperature and Mach number distributions, and reduces flow loss. It is concluded that the humpback whale fin tubercle bionic design can greatly enhance the aerodynamic performance of fan blades, and subsequent structural optimization is needed to improve the stiffness and service reliability.