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Fig. 10. Instantaneous particle traces are released from (A) a rake of rectangular
grid of points in a plane 0.75 cm away from the leading edge of the pectoral
fin and parallel to it. Using the instantaneous velocity field, the positions
of theses particles were obtained by integrating the velocity at these points
until the length of these traces exceeded a specified length, or the particles
ended on a solid boundary, or exited the computational domain. These particle
traces are colored according to the magnitude of velocity (in cm
s-1) at that location. (B) Middle of the downstroke,
t=1.064 s. (C) Beginning of the upstroke, t=1.1017 s.