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will not enter the core from any starting location.
Figure 8b-e. The diagrams show the similarity in trajectory plots for
particles with various fall speeds near a 5mm Rankine core. The four cases
correspond to the triangles in figure 8a.
Figure 9a-c. The above plates show the effect of keeping the velocity at the
core radius constant whilst increasing the core size. The graph on the right
shows the fall time for each of the trajectories in the picture on the left.
Figure 10. The pictures show a) a particle that is not captured by the core,
b) a particle that is captured and c) a particle that is just captured. The
value of AR/VT here is the criterion C below.
Figure 11. Values of the capture criterion C for various values of (X,Y), the
particle starting position at initial velocity (Vx/ VY ) = (0,0) .
Figure 12. Variation of the critical vortex strength criterion C AR/VT with
vortex radius R at constant vortex tip speed AR.
Figure 13. Time-averaged horizontal velocity induced below the mid-plane of
a moving Rankine vortex over 100 time-steps.
Figure 14. Time-averaged vertical velocity induced below the mid-plane of a
moving Rankine vortex over 100 time-steps.
Figure 15. Time-averaged horizontal velocity induced below the mid-plane of
a moving Rankine vortex over 10 time-steps.
Figure 16. Time-averaged vertical velocity induced below the mid-plane of a
moving Rankine vortex over 10 time-steps.
Figure 17. Time-averaged and time-dependent trajectories of a particle in a
moving Rankine vortex. The trajectories in the time-averaged flows are
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