A fish-like locomotion model in an ideal fluid with lateral-line-inspired background flow estimation

Considerable evidence suggests that the lateral line system serves an important role in fish-like locomotion by providing hydrodynamic information about the surrounding fluid. In this paper, a fish-like locomotion model is developed in an ideal fluid with a background flow estimation algorithm inspired by the lateral line system. Specifically, the fish model is geometrically formulated with the Joukowski transformation and is dynamically defined as a deformable solid body. Describing the fluid-body interactions is a hydrodynamic model that incorporates the potential flow theory with a shedding mechanism of discrete vortices. With the hydrodynamic information on the boundary of the fish-like profile, the background flow field can be estimated with a modified vortex panel method. Base on the estimation, the control decision can potentially be adjusted accordingly, which may improve the swimming performance. Furthermore, in the profile model, body segments are defined such that the internal forces can be easily obtained for quantitative efficiency evaluation.