Am I wrong in thinking that faster moving air is lower pressure than slow moving air? Isn't that why a wing is curved on top and not on bottom?

Anyway the reason I ask is was curious as to why the wind just blew my door open at work here. The building face is parrallel to the direction of the wind, plus there's a storm door that stayed shut. So I don't think it was caused by direct wind on the door. But it's very gusty (steady at about 20-30 mph, gusts up to 64 mph is what they're predicting). and the door opens inward. Shouldn't the air rushing past outside have caused the higher-pressure inside to close the door more tightly, instead of pushing it open a few inches? (the door was closed almost all the way but not enough to latch, so it wasn't that much force).

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I'm like one of those idiot savants...well, except for the savant part.
"In order to increase awareness of the homeless, security have been given binoculars."

Bernoulli effect, yes.

It turns out that Bernoulli effect isn't the major thing that keeps a wing in the air (otherwise, aeroplanes wouldn't be able to fly inverted), but it's an explanation that's commonly given.

A gust that blew against, rather than past, the door? Wind is flukey stuff.

Another possibility might be if you have windows or ventilation openings in the same room. The wind blowing past some other opening dropped the pressure in the room, while the screen door limited the pressure drop between the screen door and the internal door: so the door popped inwards towards the lower pressure inside the room.

Grant Hutchison

Ah, Bernoulli... couldn't think of it. His pre-cooked pasta we get in the frozen food section is pretty good to. Oh wait, that's something else

Guess it has to do with the venting and probably dynamics with the back door as well (small building, maybe 800 sq. feet). Dunno what the state of the other door was, caus i can't see it from my desk. Just thought it curious, as I would have guessed the pressure difference woulda acted in reverse of the way it did.

My only other guess was that it actually did push the door closed, but then the door hit the frame and came back due to conservation of momentum. *shrugs*

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I'm like one of those idiot savants...well, except for the savant part.
"In order to increase awareness of the homeless, security have been given binoculars."

Here's yet another possibility: the wind stopped for a moment, so the pressure equilibrium between the inside and the outside moving wind suddenly had to deal with a wind that was less, and so felt a higher pressure from the outside. Such a complicated situation! (But my gut says Grant was right the first time-- a gust or vortex hit the door, seems the most natural explanation, but who knows?)

Let's not revisit this, but suffice to say that you can explain it with Bernoulli or you can explain it with Newton (angle of attack), even though it may be neither easy nor obvious how to do so in any given situation. Using energy or using momentum is a matter of convenience, not correctness.

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"I have a cunning plan that cannot fail."
S. Baldrick

I was once unblown off my feet on an exposed ridge in the Scottish Highlands.
There was a continuous crosswise blast of wind which was beginning to propel sleet, so I'd stopped to put on a pair of waterproof overtrousers. I was balanced on one foot, leaning into the wind, when the wind just stopped, suddenly and completely. And I fell over to erstwhile windwards.

I spent the rest of the day trying to imagine the sort of change in pressure and flow that might have caused such a thing.

Grant Hutchison

Indeed, let's not.
In my first post I'd intended to suggest that Fazor could search the forum on "Bernoulli" and "lift" for more information on aeroplane wings, if interested. There have been a number of threads.

Grant Hutchison

Hey now, you're suggesting I find information for myself? You horrible person you! Don't you know it's easier to just ask in a new thread?!

Anyway door just blew open again, this time with much more force. I guess it could be the swirling wind just pushing it open directly, I just have a hard time thinking enough could get past the storm door to do so. Of course, it could also be blowing into the gap between the two doors and the increased pressure is pushing the unlatched door back. Oh well...in 28 minutes I get to lock said door and not see it again until monday. Go clock go!

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I'm like one of those idiot savants...well, except for the savant part.
"In order to increase awareness of the homeless, security have been given binoculars."

Only because the "Bernoulli effect and lift" topic seemed to be tangential to your main question.
I think swansont and I both feel that your whole thread would be hijacked if discussion started here on that topic.

Feel free. But brace yourself.

Grant Hutchison