Immersed force analysis of fish surface with carangiform locomotion

Abstract

This paper investigates the immersed forces on a fish surface during carangiform locomotion. Numerical simulations were conducted and validated to produce the immersed forces on the surface of the fish. The temporal dynamics of the immersed forces for the steady states of the fish swimming is analyzed with a comparative study based on different fish geometries and motion coefficients. The results demonstrated that under steady undulating, the immersed forces are periodically oscillating, whose magnitudes vary across the fish body. Large forces focus on the edges of the tail tips and the head of the fish during swimming, which are also the regions showing with large vorticities in the fluid. Based on the force distribution, it can be inferred that the source of the propulsion for carangiform is mainly from the rear part of the fish.