Fig. 2. Vorticity contour fields around and in the wake of the spotted boxfish
(upper row), scrawled cowfish (middle row), and buffalo trunkfish (bottom row)
models positioned at a pitch angle of +10°. The data are viewed in
transverse planes at various locations along the body and in the wake. Each
plot is the mean result of 30 paired images (1 representative trial). From
left to right, the locations, which are highlighted in the upper corner of the
figures, are: eye ridge, maximum girth, midpoint between maximum girth and
posterior edge of the carapace, posterior edge of the carapace, caudal
peduncle, and wake. The shadows beneath the models represent areas that were
shielded from laser light. White dots in scrawled cowfish and buffalo
trunkfish figures are the tips of the ventral keel extensions. Mean
circulation magnitude and mean peak vorticity magnitude for a dorsal vortex
(
D and P
D, respectively) and
ventral vortex (
V and P
V,
respectively) are included beneath the plots. In the wake of the spotted
boxfish, ventral and dorsal vortices merge and thus dorsal and ventral
distinctions are not necessary.