Quote:
Originally Posted by sc2dave
Not for corners.What i mean is, from the center of the bumper,start the airdam from there and have the ends end up in front of the wheels.
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If you take a look at the recent thread for the 2013 Chevy Malibu aerodynamics and watch the video from the wind tunnel,you'll see that the air is deforming well ahead of the cars body.This is Prandtl's line of discontinuity( My memory sucks,so watch me on this).
With just enough corner radius,the air will follow around a corner with perfectly attached flow,carrying all the useful kinetic energy rearward,hopefully to be properly decelerated in the aft-body for pressure recovery.
If you provide a 'V',the air can overshoot the corner,causing separation right then and there.
Also,it's been reported that a 'V' offers unstable acceleration compared with a curved surface within a favorable pressure regime.
Finally,the 'V' can produce local flow velocities which are incompatible with the velocity of the surrounding air mass,causing eddies and vortices to form as they meet,which cannot be harvested for kinetic energy downstream.This energy is lost forever to entropy.