Optimal design and application of bionic hydrofoil with multiple angles of attack based on genetic algorithm

The design of hydraulic machinery blades is usually conducted for optimal working conditions. Deviation from the optimal working condition indicates the presence of an angle (angle of attack) between the incoming flow and the chord length of the blade section hydrofoil. This angle causes the fluid to separate in advance during movement around the blade, which affects the uniformity of velocity distribution and reduces the performance of hydraulic machinery. In this paper, the Hicks-Henne function and the NSGA-ll genetic algorithm are used to optimize the design of the bionic hydrofoils under different angles of attack, and the optimization results of the hydrofoils under different angles of attack are averaged. The study found that: The convergence and rapidity of the NSGA-II algorithm are better than those of the NACA algorithm. The optimized hydrofoils have better lift-drag performance, its application to the blades of the water jet propulsion pump can effectively improve the head and efficiency of the pump and substantially widen the high-efficiency area of the pump. Simultaneously, the speed non-uniformity coefficient of the impeller inlet is reduced, thus improving the applicability of the pump under different operating conditions.