Something I have been musing about for a while.
The idea would be to make a tunnel suitable for testing models - I think full sized cars may be tricky. It would work based on a fish tank or similar tunnel of glass or clear plastic. At one end would be a fan, one of those area coolling ones you can get from power tool shops. The air would be ducted through the clear tunnel.
The floor of the tunnel would be raised a little and would have a small slot in it lengthways. Sticking up through this slot would be a thin but stiff piece of metal onto which the models would be attached so that they were just (perhaps a couple of mm) above the floor. Supporting the thin piece of metal would be a trolley or something on wheels which would be connected to some kitchen scales.
The idea is that when the air blows through, the resistance of the model being tested would push the trolley through the slot and move away from the wind. The amount of resistance could be calculated by measuring how much 'weight' was registered on the scales.
By the power of MSPaint:
Obviously completely barking mad.
