Most of us are familiar with Bernoulli's principle of high and low pressure areas generated by a speeding air column demonstrated with a ping pong ball held aloft by a hair dryer. A few may be aware that a balloon can be captured in the same way by a fan's air stream.
After watching this mesmerizing dance of a balloon with the fan I wondered how adding a control surface (rudder or wing) would influence the balloon. (Note: changes in orientation of the balloon can also be achieved by taping a small weight like a washer or coin to the balloon). The video shows the results of the experiment.
Possible uses of this demonstration:
- advertising might make use of a bobble head balloon - kind of mundane.
- by introducing smoke into the air stream one could utilize a free-standing wind tunnel model for the study of aerodynamics.
Or we could just have fun watching the balloon interact with the fan.