Vortex Shedding in Water

Harvard Natural Sciences Lecture Demonstrations
Harvard Natural Sciences Lecture Demonstrations
243.4 هزار بار بازدید - 12 سال پیش - Wolfgang uses a pendulum partially
Wolfgang uses a pendulum partially immersed in a makeshift flow tank to show us the effect of vortex shedding on a small object.

When fluid flows around a cylindrical object, there is a range of flow velocities for which a von Karman vortex street is formed. The shedding of these vortices imparts a small, periodic force on the object. Here the object is a cylinder attached to a physical pendulum whose frequency of oscillation is adjustable. The end of the cylinder is submerged in flowing water. When the frequency of the pendulum is adjusted to match the frequency of vortex shedding, the cylinder swings transverse to the direction of flow with a peak-to-peak amplitude of a few centimeters.

For more details on our setup as well as references for further study see http://sciencedemonstrations.fas.harv...
12 سال پیش در تاریخ 1391/04/02 منتشر شده است.
243,468 بـار بازدید شده
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