The 12th International Conference on Hydrodynamics
18 – 23 september 2016, Egmond aan Zee, The Netherlands
Home Program Author Index Search

FLUID DYNAMICS OF A SELF-PROPELLED FLAPPING PECTORAL FIN BY FLUID-MOTION COUPLING IMMERSED BOUNDARY METHOD


Go-down ichd2016 Tracking Number 71

Presentation:
Session: Computational Fluid Dynamics II
Room: Room 2
Session start: 14:00 Mon 19 Sep 2016

Ningyu Li   liningyu123@aliyun.com
Affifliation: Science and Technology on Underwater Vehicle Laboratory, Harbin Engineering University, Harbin, 150001, China

Yumin Su   suyumin@hrbeu.edu.cn
Affifliation: Science and Technology on Underwater Vehicle Laboratory, Harbin Engineering University, Harbin, 150001, China

Weixing Liu   lwx19900117@163.com
Affifliation: Science and Technology on Underwater Vehicle Laboratory, Harbin Engineering University, Harbin, 150001, China


Topics: - Computational fluid dynamics, - Bio fluid mechanics

Abstract:

Dynamical behaviors of a self-propelled flapping pectoral fin are investigated by developed immersed boundary (IB) method, in which a robust numerical strategy is proposed to deal with complex moving boundaries involved in biomimetic flow simulations and the fluid-motion coupling is embodied. The fin is modeled as a pectoral-fin-shaped flapping plate with a freedom in the horizontal direction. We have investigated the unsteady process of the fin locomotion and corresponding mechanisms in detail and compared the complex-shaped low-aspect-ratio fin with symmetric foils. A parametric study is also carried out to discuss the effect of key governing parameters. The results show that the fin can reach the fully developed state earlier and induce faster lateral velocity with increasing flapping frequency or flapping amplitude. Moreover, the linear relationship between translational Reynolds number and frequency Reynolds number is found as the latter is over a critical value. As the flapping amplitude is raised, the translational Reynolds number rapidly increases in an approximately linear way, and thereafter a relatively slow growing trend is observed.