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horizontal before falling away from the core.
Figure 5. The effect that changing the particle fall speed has on the
position of the central capture region of the parameter space for vortex
growth rate G=0.01m/s.
Figure 6. The effect of changing the shear layer growth rate G on the
position of the central capture region of the parameter space for particle
fall speed V=0.076 m/s.
Figure 7. Comparisons between the above equation and data for the lower
parameter space line at different values of particle fall speed and vortex
growth rate.
Figure 8. Comparisons between the above equation and data for the upper
parameter space line at different values of particle fall speed and vortex
growth rate.
Chapter 7
Figure la-g. The seven trajectory modes for jetted particles, a) Ml b) M2 c)
M3 d) M4 e) M5 f) M6 g) M7.
Figure 2. The plates show three views of the recirculation region behind an
experimental bedform. The shots are 0.35 sees, apart and clearly visualise
the sweeping away of the turbulent region, leading to re-attachment close to
the trough. We term this sequence of events Coanda-flapping.
Figure 3a-j . The plates show particles transported by periodic flows caused
by Coanda-flapping of the free shear layer. The particles (dark spots, just
off centre-line of the rig and light spots on the centre line) have a fall
speed of 0.034m/s and depth-averaged flow speed is 0.31m/s.
Figure 4. Values of the capture criterion for various values of particle
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