Kinematic and wake parameters during locomotion by Scomber japonicus at speeds of 1.2 and 2.2 FLs-1
| 1.2 FLs-1 | 2.2 FLs-1 | |||
|---|---|---|---|---|
| Parameter | Horizontala | Verticala | Horizontalb | Verticalc |
| Stroke duration (ms) | 200±24 | — | 119±8 | — |
| Body angle to horizontal (degrees) | — | -3±4 | — | -4±4 |
| Vortex radius (cm) | 0.82±0.26 | 0.78±0.23 | 0.93±0.08 | 0.83±0.26 |
| Distance between vortex centers (cm) | 5.49±0.71 | 3.25±0.66 | 6.79±1.05 | 3.54±0.49 |
| Ring axis angle (degrees) | 34±10 | 86±13 | 27±5 | 91±7 |
| Jet angle (degrees) | 67±9 | -3±5 | 53±12 | -2±4 |
| Circulation (cm2 s-1) | 31±9 | 15±8 | 52±8 | 27±11 |
| Momentum (g cm2 s-1) | 437±123 | 210±110 | 1001±157 | 529±208 |
| Lateral force (mN) | 22±6 | — | 65±14 | — |
| Vertical force (mN) | — | -1±1 | — | -1±2 |
| Downstream force (mN) | 10±5 | 11±6 | 50±16 | 44±17 |
| Mean downstream force/mean lateral force | 0.5 | NA | 0.77 | NA |
| Total force (mN) | 24±7 | 11±6 | 84±13 | 44±17 |
Values are presented as means ± S.D.
FL, fork length.
NA, not applicable.
↵ a N=20 (five strokes from each of four fish); bN=12 (at least one stroke from each of four fish); cN=7 (at least one stroke from each of four fish).