Exhibit: Flow Tank

The tank is like a wind tunnel and you can see the lines of flow as fluid moves past objects of various shapes.  Move the objects in the tank using magnets to see how ‘aerodynamic’ they are.  The fluid in the tank contains tiny flat crystals of a shiny mineral, mica, which show up the flow lines as it speeds across the tank.  The speed of the flow is set to give smooth flow-lines – if it is too fast, the flow becomes turbulent.  The plastic shapes are nearly as wide as the tank, so the fluid can only flow above and below them.  There are magnets embedded in the shapes so that they can be moved on the outside of the tank.  Explore the differences between laminar and turbulent flow.