Quote:
Originally Posted by twinair
My statement isn't about streamlining, it's about the effect of the distance between road surface and bottom of a parallel surface on pure shear forces (and that these shear forces wouldn't be substantial, since it is not practical to lower the car to a point, where these shear forces would start to play a significant role).
Maybe there are other detrimental effects than increased shear forces which may start to play a role when lowering a car.
Can you show any data that shows that lowering a passenger car has increased aerodynamic resistance?
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Copy-Pro,here where I use the computer is closing for the Thanksgiving holiday,so it will be next week before I can bring anything.
If you can get a look at any of Hucho's books,you'll find a section on 'Effective-Bluffness','Effective-Fineness Ratio',which examines the role ground clearance plays with Cd.The Schl'o'rwagen is investigated completely for G.C. effects.
You'll notice that,for instance,the 'Aerodynamic Streamlining Template' would have a Cd 0.08 on the ground with it's wheels completely retracted into it's body,rather than Cd 0.13 or so with ground clearance.
*Lowering effectively increases fineness ratio.
*It also reduces the frontal area by virtue of shielding the wheels/tires.
*It can affect body drag optimization by virtue of inclination/rake effects,as with both Ford Probe-IV and V which are both lowered and 'raked' for lowest drag.
I'll catch up next week.
We are cautioned to investigate vehicles on a case-specific basis,so we'd be remiss to attempt blanket statements.