Research
This research gives a new twist to a 100-year old problem in the theory of vortex motion.
A E H Love (1863-1940)
In 1894, Love showed that two identical
vortex pairs can engage in a perpetual leapfrogging motion, but it now
turns out that this motion can be unstable, in a very curious way.
"Walkabout" instability of vortex leapfrogging
The research is described in European Journal of
Physics Vol. 21, pp 269-273 (2000), and the animation
software
leapfrog.zip has been specially written to accompany that
paper.
Download and unzip, or, alternatively click on the individual, ready-to-run programs
LEAP1.EXE
contains pre-set animations of vortex leapfrogging
LEAP2.EXE
shows the corresponding vortex trajectories
LEAP3.EXE
allows the user to try different parameter values
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