Dynamics of prolate jellyfish with a jet-based locomotion |
| |
| Institution: | 1. Department of Mechanical Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea;2. Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China;1. Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China;2. School of Life Sciences, University of Science and Technology of China, Hefei 230027, China;1. Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, Department of Mechanics and Engineering Structure, Wuhan University of Technology, Wuhan, 430070, China;2. School of Marine and Energy Power Engineering, Wuhan University of Technology, Wuhan, 430063, Hubei, China;3. Department of Ocean Technology, Policy and Environment, The University of Tokyo, Tokyo, 1538505, Japan;1. Naval Architecture & Marine Engineering, U.S. Coast Guard Academy, 27 Mohegan Avenue, New London, CT 06320, USA;2. Naval Architecture & Marine Engineering, Director Marine Renewable Energy Laboratory, University of Michigan, 2600 Draper Drive, Ann Arbor, MI 48109, USA |
| |
| Abstract: | Swimming jellyfish deliver momentum to the surrounding fluid in the form of vortices. A three-dimensional computational model was adopted to investigate the characteristic flow patterns produced by jellyfish with a jet-based locomotion and the process of vortex generation. The interaction between jellyfish and the surrounding fluid may be simulated using the immersed boundary method. The vortex structures generated in the wake were elucidated in detail. The vortices were formed due to the contraction and expansion of the elastic bell. A dimensionless temporal parameter was employed to analyze the vortex formation process. During the early stage of contraction, the vortices were dominantly generated by the stroke. The ejected fluid from the inside of the bell was then entrained into the vortices, thereby decreasing the vorticity at the core and increasing the total circulation within the vortex ring. The Froude propulsion efficiency increased as the vortex formation number increased, implying that the propulsion in the way of growing the vortex structures was favorable in terms of the efficiency. |
| |
| Keywords: | Flow–structure interaction Swimming/flying Propulsion Vortex dynamics |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
