Quote:
Originally Posted by freebeard
The top of the fender is a simple case, the interior of the wheelwell not so much. I'm reminded of the https://duckduckgo.com/?q=hollow+cylinder+shear+test.
The top of the tire is moving twice as fast in the opposite direction. The shape and free space inside the wheelwell cavity will have a lot of influence. As will the presence or absence of an air curtain or skirt. |
* The 'surface-feet-per-minute' of the tire tread is identical to the ground speed of the vehicle.
* That puts the top of the tire, 'if exposed' to the airstream, attacking the surrounding calm air, at the same speed as the vehicle, while the bottom of the tire is retreating away from the surrounding air mass.
* With an 'enclosed' body, airflow conditions within a wheel cavity would be highly 'conditional,' as mentioned, so no 'one-size-fits-all' characterizations allowed.
* Wheel-related aerodynamics could be reduced to 'windage'- ' ventilation drag .'
* Caveats .