Author(s)

Yusheng Liu, Tao Zhou, Xingjian Lin^*

School of Mechanical Engineering, Nanjing Institute of Technology, Nanjing, China.

The underlying mechanisms driving the efficient propulsion of fish remain incompletely understood. In this study, fish is simplified as hydrofoil with two degrees of freedom in two-dimensional flow, the effects of flapping frequency and wavelength on propulsion performance of a hydrofoil are numerically studied. It is found that the propulsion velocity increases monotonically with the rise of frequency, while it varies non-linearly with wavelength variation. However, the efficiency demonstrates contrasting trends—increasing monotonically with frequency elevation while decreasing progressively with wavelength extension. Notably, optimal performance is achieved at a flapping frequency of $f$ = 2 and wavelength λ = 1.5. The results here may shed some lights on the understanding of the efficient swimming of fish.

Fish Swimming, Fluid Simulation

Liu, Y. , Zhou, T. and Lin, X. (2025) Numerical Study on the Two-Dimensional Self-Propulsion of a Hydrofoil. Journal of Applied Mathematics and Physics, 13, 1514-1522. doi: 10.4236/jamp.2025.134081.