Quote:
Originally Posted by ryannoe
... vortex generators re-energize boundary layers. Why would you think to energize a laminar boundary layer? Laminar skin friction is the least drag of any type and the least your worries. Never interrupt that flow with a vortex generator. Vortex generators are used to keep the turbulent boundary layer attached longer, thus reducing pressure drag and to give control surfaces authority ...
|
In some cases laminar flow does cause more drag than turbulent flow, especially so when it meets a surface that curls away in the wrong direction.
The Coanda effect will cause laminar flow to follow that surface, while turbulent flow will by and large move on in the same direction.
Most cars have curved edges on their rear bumpers. In a straight headwind the airflow along its sides will be turbulent, but when hit by sidewind it will be more or less laminar, curve round the bumper and create low pressure on the edge pulling it sideways and back.
I am planning to put zigzag tape on my 2011 Insight's rear bumper just ahead of the curve to break laminar flow. If that stops the jerking sensation when hit by sidewind then I will know that it works.
__________________
2011 Honda Insight + HID, LEDs, tiny PV panel, extra brake pad return springs, neutral wheel alignment, 44/42 PSI (air), PHEV light (inop), tightened wheel nut.
lifetime FE over 0.2 Gmeter or 0.13 Mmile.
For confirmation go to people just like you.
For education go to people unlike yourself.