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Tyre grip

  1. Apr 16, 2004 #1
    If tyres are deeply grooved and a high speed jet of air was deliberately sprayed into the grooves , could this enhance the grip via pressure reduction
    or does it result in an increase in pressure and decrease in grip?
  2. jcsd
  3. Apr 16, 2004 #2


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    I think it would create same effect the Venturi pipe. So that the grip would be increased. But:
    -I have doubts about its industrial applications.
    -F1 cars have a Venturi pipe at its bottom. This is called the "ground effect". It enhances a better structural grip to the floor and counteracts lifting.
  4. Apr 17, 2004 #3


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    Well, if you created the high speed jet of air by 'spraying' it onto the tires, that implies you're using a high pressure source. Since you end up with a still higher pressure than atmospheric you lose traction, albeit a small amount since the surface area is small.

    If it were simply the displacement of the air by the tire the amount of turbulence is going to be quite large so any laminar flow of air discussion at the level of tread depth is likely a waste of time. And again, this is especially true when a adequate surface area is needed for a pressure drop to become effective like the size of the wing on an aircraft.

  5. Apr 17, 2004 #4
    What about channeling atmospheric air through the bodywork on to the bottom of the tyres? Could get low pressure air that way.
  6. Apr 20, 2004 #5


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    You still have two problems:

    1. Small surface area. This is like saying you can generate downforce on your car when you stick your hand out the window and make your fingers flat and pitch it at say a 45 degree angle. Sure you can feel the wind's effect on your hands, but it that going to change the tire's loading enough to measure it? What if it was just a business card? How big is a tire's contact patch (not very big, 20 sq in) and then how much of that contact patch would the grooves occupy, maybe 15%?

    2. Turbulence. Think of an aircraft wing pitched with an attitude too steep where it goes into stall.

  7. Apr 20, 2004 #6
    What if a jet of air was used to force water from under a tyre when road conditions are bad? That could help improve grip.
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