Optimization design of the unsmooth bionic structure of a hydrofoil leading edge based on the Grey–Taguchi method

Abstract

Hydrofoil sections are broadly used in the field of fluid machinery. The leading edge of a hydrofoil structure is closely related to drag and cavitation performance. In this study, we adopt the concept of a bionic design. The fin structure of a fish is simplified and applied to the traditional National Advisory Committee for Aeronautics 0015 hydrofoil. We adopt the Grey–Taguchi method to calculate the best layout. This helps obtain the best drag and cavitation performance. Large eddy simulations are used to verify the scheme. When the ratio of fin depth to length h/L is 0.3, the fin layout length X_n is 7 L, the inclination of fins θ is 7°, and the bionic hydrofoil exhibits the best hydrodynamic performance. Application of the best bionic hydrofoil to the fluid machinery (pump) demonstrates that the hydraulic performance of the pump has been considerably improved.