MÜLler U, Heuvel B, Stamhuis E, Videler J
J Exp Biol. 1997;200(Pt 22):2893-906. doi: 10.1242/jeb.200.22.2893.
The structure of the wake behind a continuously swimming mullet was analysed qualitatively and quantitatively by applying two-dimensional particle image velocimetry. A detailed analysis of the flow pattern and of the swimming movements of the fish allowed us to derive a kinematic explanation of the flow pattern as well as an estimate of the relative contributions of the body and the tail to thrust production. During active propulsion, the undulatory swimming fish shed a wake consisting in the medio-frontal plane of a rearward, zigzagging jet flow between alternating vortices. The fish shed one vortex per half tailbeat when the tail reached its most lateral position. Part of the circulation shed in the vortices had been generated previously on the body by the transverse body wave travelling down the body. This undulatory pump mechanism accounted for less than half of the energy shed in the wake. The remainder was generated by the tail. The vortex spacing matched the tailbeat amplitude and the stride length.
通过应用二维粒子图像测速技术，对持续游动的鲻鱼身后的尾流结构进行了定性和定量分析。对鱼的流动模式和游动动作的详细分析，使我们能够得出流动模式的运动学解释，以及身体和尾巴对推力产生的相对贡献的估计。在主动推进过程中，波动游动的鱼在中额平面上产生一个尾流，该尾流由交替涡旋之间向后的锯齿状射流组成。当尾巴到达其最外侧位置时，鱼每半个尾拍产生一个涡旋。涡旋中脱落的部分环流先前是由沿身体向下传播的横向体波在身体上产生的。这种波动泵机制占尾流中释放能量的不到一半。其余的能量由尾巴产生。涡旋间距与尾拍幅度和步长相匹配。
