Research on the Undulatory Motion Mechanism of Seahorse Based on Dynamic Mesh

Abstract

The seahorse relies on the undulatory motion of the dorsal fin to generate thrust, which makes it possess quite high maneuverability and efficiency, and due to its low volume of the dorsal fin, it is conducive to the study of miniaturization of the driving mechanism. This paper carried out a study on the undulatory motion mechanism of the seahorse’s dorsal fin and proposed a dynamic model of the interaction between the seahorse’s dorsal fin and seawater based on the hydrodynamic properties of seawater and the theory of fluid-structure coupling. A simulation model was established using the Fluent software, and the 3D fluid dynamic mesh was used to study the undulatory motion mechanism of the seahorse’s dorsal fin. The effect of the swing frequency, amplitude, and wavelength of the seahorse’s dorsal fin on its propulsion performance was studied. On this basis, an optimized design method was used to design a bionic seahorse’s dorsal fin undulatory motion mechanism. The paper has important guiding significance for the research and miniaturization of new underwater vehicles.

Inspired by the Black Ghost Knifefish: Bionic Design of Undulatory Fin with 2-DOF Rays and Its Propulsion Performance

“…The low-speed maneuverability and hovering performance of undulatory fin propulsion are very inline with the current needs of ocean engineering for operation in complex environment. Therefore, research institutions such as Northwestern University and Nanyang University of Technology have studied various organisms which swim by means of an undulating fin, such as manta ray [9][10][11], stingray [12], black ghost knifefish [13,14], Rhinoptera javanica [15], and seahorse [16]. The various approaches they employed encompass analysis of kinematic data from live swimming fish [17], computational fluid dynamics (CFD) studies [13,18,19], and theoretical modeling [4,20,21].…”