Spin up and down of vortices

Rotating water in a container

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Water tank
2 household plastic cylindrical containers
Diameter: approx. 12cm
Height: approx. 14cm

In one, the 4 rotating blades are placed in a cross in the middle of the base of the container. In the other container, the blades are placed evenly around the perimeter.

Working fluid
Water
 
Visualization
Styrene beads are mixed into the water, and a slide projector is used to light up the tank from the side. The tanks are then photographed with a stationary camera.
 
Experimental process
Water was placed in the containers, which were then placed in turn on the rotating table and rotated.