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Old 05-28-2011, 02:59 PM   #42 (permalink)
robchalmers
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Quote:
Originally Posted by winkosmosis View Post
An analog would be a car... Remember the Audi TT lift fiasco? Even at zero chord angle, a car can have dangerous lift, necessitating spoilers. It's not because air flows faster over the top of the car, but because of the angle of the sloping windshield and trunk. If it was Bernoulli, the little spoiler that they added to the trunk wouldn't have solved the issue.




Heck... if Bernoulli was that powerful, cars with air dams preventing much airflow underneath would lift off.
oh dear.

first the audi solution generates seperation to kill lift a the rear most point, the phase 1 TT still generats lift, just not as much.

as for airdams they limit the flow under the car which is accelerated as it leave the underside and resumes normal flow therefore the flow is faster than the upper surface .

I thinking you really need to seperate Benoullis law from the longer line theory.
lift is resultant from benoulli lift and downwash lift
nealy every single car on the road produces lift.

if you don't fancy the paper trick mentioned earlier try hanging a spoon between you forefinger and thumb with the head hanging down loose enough to wobble. now run your fosset and put the curve back into the flow. ok, now repeat with the dished inner side - 9times out of 10 depening on the spoon the back will get more movement than the dish.

Benoulli works - long line is Boll***s
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