"leading aerodynamicist Doug McLean has attempted to go beyond sheer mathematical formalism and come to grips with the physical cause-and-effect relations that account for lift in all of its real-life manifestations. … McLean’s complex explanation of lift starts with the basic assumption of all ordinary aerodynamics: the air around a wing acts as “a continuous material that deforms to follow the contours of the airfoil.” That deformation exists in the form of a deep swath of fluid flow both above and below the wing. “The airfoil affects the pressure over a wide area in what is called a pressure field,” McLean writes. “When lift is produced, a diffuse cloud of low pressure always forms above the airfoil, and a diffuse cloud of high pressure usually forms below. Where these clouds touch the airfoil they constitute the pressure difference that exerts lift on the airfoil.”

The wing pushes the air down, resulting in a downward turn of the airflow. The air above the wing is sped up in accordance with Bernoulli’s principle. In addition, there is an area of high pressure below the wing and a region of low pressure above. This means that there are four necessary components in McLean’s explanation of lift: a downward turning of the airflow, an increase in the airflow’s speed, an area of low pressure and an area of high pressure.

But it is the interrelation among these four elements that is the most novel and distinctive aspect of McLean’s account. “They support each other in a reciprocal cause-and-effect relationship, and none would exist without the others,” he writes. “The pressure differences exert the lift force on the airfoil, while the downward turning of the flow and the changes in flow speed sustain the pressure differences.” It is this interrelation that constitutes a fifth element of McLean’s explanation: the reciprocity among the other four. It is as if those four components collectively bring themselves into existence, and sustain themselves, by simultaneous acts of mutual creation and causation."

25 points

Maybe no one in your social circle can.

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-11 points
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While taking King’s Pilot School class I was taught that Bernoulli’s Principal explains how planes generate lift. But a few months later I saw someone post online who said that it is actually debated whether this is true. I thought it was interesting and have been thinking about it lately. A little research found this article in Scientific American which describes the ongoing debate.

And why do you have to be so rude?

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32 points

I get annoyed at clickbait titles.

It’s quite obvious Bernouilli’s theorem is largely correct, even though it does not cover the entirety of why air behaves like this.

Planes stay in the air because of aerodynamic lift. Planes are designed around this principle and thousands of planes stay in the air because we know this is how it works.

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3 points
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To be clear I have no idea either way.

Is this one of those “we know what the principle is (aerodynamic lift) and how to make it work but we don’t know why it works the way it does?”

edit. ask question. receive downvotes. Hello reddit 2.0.

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10 points

Oh boy, you’re going to be really surprised when you learn how steel ships float.

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0 points
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Wing diverts air down

Newton’s 3rd law means wing goes up

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4 points

That is not, in fact, how aerodynamic lift works.

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-1 points

Sure it is.

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0 points

It’s really not. The longer travel of the air over the top of the wing creates an area of lower pressure than the air flowing under the wing, effectively “pushing” the wing upward.

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-1 points
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Deleted by creator
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18 points
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Because it is clickbate we know the general principles as to why aircraft work but not 100%.

It is like saying you don’t know how a week works because you can’t tell me what day Dinsdag is.

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14 points

Doesn’t really matter how high quality the piece is. The title is too clickbaity. Everyone here on Lemmy is here because we fled shitty internet practices at some point, so we’re fairly sensitive to things like sensational wording. I’m guessing most downvoters did not click the link.

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note: clickbait sources/headlines aren’t liked generally. I’ve posted crap sources and later deleted or edit to improve after complaints. whoops, sry

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