Orange peel-jet
How fast do droplets generated from the squeezing of an orange peel travel?
Fig 1
Materials and Methods
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We took one of the best-looking orange from the supermarket (Fig. 1).
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Bending the peel while recording at 20000 fps with a high-speed camera (Video 1).
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We used trackMate plugin in ImageJ to track the droplets [1].
Video 1
Results
Video 1 shows the droplets fired from the orange peel. The droplets with the coloured contours are tracked. The other droplets are too fast to be tracked.
In Fig. 2, we plot the average velocity (v) of the tracked droplets over time (t ). The time at the end of the recording is t_end.
The maximum recorded velocity is ~6000 mm/s (~21.6 km/h). This speed is in close agreement with a previous report [2]. Although faster droplets are fired up from the orange peel, they can not be tracked due to motion strike.
We note that as the time goes on, the average velocity decreases. This is probably associated with fluid depletion in the oil gland reservoirs.