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No programming in this at all, but I figure there are some physics geeks amongst the crowd.
Here's the situation: My general lunch routine recently has been to be eating at a picnic table on the Jersey City boardwalk, overlooking the Hudson river --- none of that is particular relevant except to say, it's a bit windy.
Somedays I eat a pizza, which is served in a small flat box. After I finish eating, I'll sit at the table and read for a while, before packing up my thing, throwing out the garbage, and returning to work.
During this point, I don't want the box blowing away, so I close of the box so it's a flat as possible.
Now, the question: Have I made the box MORE aerodynamic, or LESS?
The immediate goal is to allow the wind to pass smoothly over the box, instead of dragging it away, which would be MORE aerodynamic.
But the overall goal is to prevent it from flying away, which would mean LESS aerodynamic....
Truth,
James
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IMO, a pizza box is too light to consider aerodynamics. What you really want is to decrease the surface area of the box on which the wind can apply any Pressure.
Since Force = Pressure x Area, considering the pressure by the wind is a constant, the lesser the area the lesser the force applied on the box hence, the lesser the chances that the wind will move it, given that the pressure is not too much.
I am not the one who knocks. I never knock.
In fact, I hate knocking.
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What you should be doing is forming it into an inverted wing - do that instead of generating lift, it creates downforce, "sucking" it onto the table and increasing the friction, thus preventing it from getting blown away.
Naturally, you will need to design this for the prevailing wind speed range and direction to get a noticeable effect.
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Way to spend the lunch break
I am not the one who knocks. I never knock.
In fact, I hate knocking.
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You would not need to make it a wing shape, just put it on some supports, leaving a small gap between it an the table.
Air will accelerate through this gap, and, as Bernoulis law dictates, the pressure in the gap will be reduced.
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Assuming the downforce generated is greater than the force against the flat leading edge.
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If the box were flat on the table it would have blown off.
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I suppose the OP's question could be answered by how it came off. If it "slid off" due to the wind it isn't aerodynamic. If it "flew off" then it is aerodynamic.
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RandyBuchholz wrote: If it "flew off" then it is aerodynamic
That is not the definition of 'aerodynamic'. Aerodynamic means the shape produces low drag.
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Guess I'll have to start adding smilies to my attempts...
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Always helpful!
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Like this?[^] Bonus points if you can adjust the angle of attack.
And the notebook should play Wagner when it uses its new stabilizers.
I am endeavoring, ma'am, to construct a mnemonic memory circuit using stone knives and bearskins.
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OriginalGriff wrote: What you should be doing is forming it into an inverted wing
Exactly what I was going to suggest! Two great minds, a single thought between them.
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If when opened and flat the box has a two vertical lips.
This creates two surfaces to catch the wind and will create more force.
Closed, as a box, there is only the front surface to catch the wind.
So closed = more aerodynamic.
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Picnic tables tend to be wood so carry a pointy knife and shove it through the cardboard and into the wood - problem solved, that sucker is not going to fly away.
Never underestimate the power of human stupidity
RAH
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Be careful not to turn it into an airfoil.
I am endeavoring, ma'am, to construct a mnemonic memory circuit using stone knives and bearskins.
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Put a rock in it
Someone's therapist knows all about you!
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Pragmatic, nice.
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Realistic
1) Nobody is going to spend the time to craft an inverted wing.
2) As light as the box is the box will probably blow away anyway.
3) Without proper adult supervision my girl friend won't let me use a knife.
Someone's therapist knows all about you!
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Or your cellphone. What could possibly go wrong?
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Absolutely what could go wrong?
Someone's therapist knows all about you!
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James Curran wrote: on the Jersey City boardwalk, overlooking the Hudson river
I was there a couple weekends ago! My gf and I took a nice evening stroll and enjoyed the nightscape after eating dinner at Amiya - Contemporary Indian Cuisine
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The question is, "Is it more aerodynamically efficient or less?"
You can't say something is or is not "aerodynamic".
The difficult we do right away...
...the impossible takes slightly longer.
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James Curran wrote: it's a bit windy...Have I made the box MORE aerodynamic, or LESS?
At least for me "a bit windy" means that box is going to go sailing regardless of what it looks like. Or at least it will start moving which will interrupt me as I grab for it.
Collapse it completely and then fold it up and stick it under your leg. It won't go anywhere.
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