Morphological features and functions of bluefin tuna change with growth |
| |
| Authors: | Yumiko Tamura Tsutomu Takagi |
| |
| Institution: | (1) Graduate School of Agriculture, Kinki University, Nara Nara, 631-8505, Japan |
| |
| Abstract: | Morphological features of Pacific bluefin tuna Thunnus orientalis have important functions for its fast swimming. Morphological features of tuna change with growth; therefore, morphological
functions may develop during this process. In this study, we precisely quantified the morphology of bluefin tuna with growth
from juvenile to young adult using a three-dimensional laser profiler and evaluated the fluid dynamic characteristics of tuna
using computational fluid dynamics (CFD) and an accurate model based on measured data. As results of measurement of morphological
features, the aspect ratio and sweepback angle, which are indices of hydrodynamic characteristics for a hydrofoil, suggested
that the lift force of caudal fin was increased as the tuna grows. The results of CFD analysis showed that the coefficient
of drag force gradually decreased with growth. Pectoral fins generated lift force, and the ratio of lift force to submerged
weight (FL/SW) increased as the tuna grew to 0.2 m total length (TL). After the tuna exceeded 0.2 m TL, FL/SW changed to a
wider range in angle of attack as the tuna grew. These results suggest that the morphological function of bluefin tuna develops
to enhance its swimming ability as it grows from juvenile to young adult. |
| |
| Keywords: | CFD analysis Fluid dynamics Growth Morphological feature Morphological function |
| 本文献已被 SpringerLink 等数据库收录！ |
|
