鱼的运动：柔性类箔鳍的动力学与流体力学研究

New experimental kinematic and hydrodynamic
data are presented for pectoral fin function in bluegill
sunfish. The highly flexible sunfish pectoral fin moves in a
complex manner with two leading edges, a spanwise wave
of bending, and substantial changes in area through the fin
beat cycle. Data from scanning particle image velocimetry
(PIV) and time-resolved stereo PIV show that the pectoral
fin generates thrust throughout the fin beat cycle, and that
there is no time of net drag. Continuous thrust production is
due to fin flexibility which enables some part of the fin to
generate thrust at all times and to smooth out oscillations
that might arise at the transition from outstroke to instroke
during the movement cycle. Computational fluid dynamic
analyses of sunfish pectoral fin function corroborate this
conclusion. Future research on fish fin function will benefit
considerably from close integration with studies of robotic
model fins. 德国LaVision PIV/PLIF粒子成像测速场仪