In early impulse turbines such as the Laval turbine and recoil turbines such as the Parsons turbine, the impeller is the core component, and its efficiency is related to the complexity of the blade structure.
Impeller design has undergone a transformation from relying on empirical formulas and manual drawings to introducing digital simulation technologies such as computational fluid dynamics and structural dynamics.
In the early 1950s, Wu Zhonghua established the three-dimensional flow theory of turbomachinery (S1, S2 flow surface theory), which has been applied in the design of turbines for the Three Gorges Dam project in my country. [10] Modern aerospace and other fields use three-dimensional flow surface design for impellers, and through simulation optimization of the flow channel, the hydraulic efficiency is significantly improved compared with empirical design (e.g., more than 30%).
Currently, impeller technology is transforming towards green and electricization, including the development of low-noise and low-consumption designs, and the exploration of composite materials, hydrogen fuel-compatible impellers, and topology optimization technology based on machine learning.