Open AccessSimulation and Functional Mechanism of Tuna Median Fins on Yaw Mobility in Unsteady Flow
Author(s) -
Xiaohu Li,
Lei Weng,
Gao J
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1746/1/012010
Subject(s) - tuna , lift (data mining) , marine engineering , wake , mechanics , yellowfin tuna , flow (mathematics) , simulation , fish <actinopterygii> , physics , fishery , engineering , computer science , biology , data mining
Tuna keeps its median fins erect in searching and feeding behaviors. During the process of these behaviors, tuna probably needs to yaw frequently in the wake of a shoal of small fish. This paper aims to clarify the functional mechanism of the erected median fins on yaw mobility in unsteady flow. Firstly, the CAD simulation models with two morphing states of the median fins are constructed by scanning and measuring the physical prototype of real yellowfin tuna. Secondly, the wake environment of the fish school is created by swinging a tuna model back and forth. Lastly, the hydrodynamic analysis of different morphing states of tuna median fins in unsteady flow is carried out. The results show that the lift forces of the median fins increases in the erection state to a certain extent, which is beneficial to the tuna’s yaw motions. Moreover, the hydrodynamics of the tuna’s body also rise due to the interaction between the body and the median fins. This further improves the yaw mobility of the tuna in unsteady flow.