Air Velocity vs generated Pressure

1. Sep 11, 2007

Farid

I have a simple question, can any one please help. It goes something like this:
if wind is blowing at a velocity of 80 mph against a 2" X 2" plate, how much pressure (or force) is brought upon the plate?
would appreciate the formula, if any.
Thank you.

Farid

2. Sep 11, 2007

Staff: Mentor

Sounds like homework. Do you have any idea how you might find the answer?

3. Sep 11, 2007

Farid

Hi Russ,
No, it is not really homework. It is my project at work. However, the surface is area is more complex than I proposed above (2"x2"). Once I know, what method to use, then I can plug in the real "area".
I was going to find Pressure from the Bernoulie Eq. :
dynamic pressure = q= (roh*V^2)/2 or, q=.000256*V^2 [psf]
Once I know the pressure, then I can find the F=p/a, that my surface will be subjected to.
Right?

Farid

4. Sep 12, 2007

Staff: Mentor

You are correct. A flat plate in a uniform airstream essentially converts all velocity pressure to static pressure via Bernoulli's eq.

5. Sep 12, 2007

Farid

Thank you.

Farid

6. Sep 21, 2007

stewartcs

NO, Force does not equal Pressure divided by Area. Force is equal to Pressure times Area.

P = F/A which gives F = P*A

CS

7. Sep 21, 2007

Staff: Mentor

D'oh. Missed that, thanks.

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