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Aeroplane wing structure -- airflow question
In summary, the speed of air is faster on top of an airplane wing, which results in a net downward motion of the air and a lift force on the wing. This is due to the complicated process of computational fluid dynamics and the Coanda Effect. For more information and a detailed explanation of lift, you can refer to the Insights article titled "Airplane Wing at Work: A Primer on Lift" by member @boneh3ad.
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russ_watters
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The air does not meet at point b simultaneously - in fact the air above the wing gets there first. Does your text explicitly say something about this?Hemant said:
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A.T.
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It doesn't. See 25sec into this video:Hemant said:
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- #5
berkeman
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Can you provide a link to that text, or at least the title and author and edition? Thanks.Hemant said:
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Frigus
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Sir I got this text from my coaching institute.berkeman said:Can you provide a link to that text, or at least the title and author and edition? Thanks.
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berkeman
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Hemant said:
Well, since it is suspect at this point, it would be good to get more information about it so we can figure out if the person putting it together doesn't understand the subject really well, or if perhaps there is some other issue with your/our understanding of what they wrote.
Perhaps you could forward a link to this PF thread to your "coaching institute" to see if they have a response? Thanks.
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Frigus
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Can anyone explain me why the speed of air splitted on top has more speed.
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- #9
FactChecker
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You will see many intuitively simple explanations of lift. They are all wrong or at least incomplete. The real explanation of the lift force is unsatisfyingly complicated.
If small packets of air are traced along so that they satisfy all the physics equations (a very complicated process of computational fluid dynamics (CFD)), they end up with a net downward motion after the wing has passed. They also travel faster over the top and reach the trailing edge sooner than the packets beneath the wing. The net downward motion of the air is an action for which the equal and opposite reaction is a lift force on the wing.
Here is a Youtube video, referencing the Coanda Effect, that might interest you.
PS. The motion of the air also exerts a nose-down rotational moment on the wing.
If small packets of air are traced along so that they satisfy all the physics equations (a very complicated process of computational fluid dynamics (CFD)), they end up with a net downward motion after the wing has passed. They also travel faster over the top and reach the trailing edge sooner than the packets beneath the wing. The net downward motion of the air is an action for which the equal and opposite reaction is a lift force on the wing.
Here is a Youtube video, referencing the Coanda Effect, that might interest you.
PS. The motion of the air also exerts a nose-down rotational moment on the wing.
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- #10
berkeman
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We have some Insights articles that may help you learn about lift. This one by member @boneh3ad is a good one to start with:Hemant said:
https://www.physicsforums.com/insights/airplane-wing-work-primer-lift/
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Frigus
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Thanks to all 
1. How does an aeroplane wing generate lift?
The shape of the aeroplane wing, known as an airfoil, is designed to create a pressure difference between the top and bottom surfaces of the wing. The curved shape of the wing causes air to move faster over the top, creating lower pressure and thus generating lift.
2. What is the angle of attack and how does it affect the airflow over the wing?
The angle of attack refers to the angle at which the wing meets the oncoming air. As the angle of attack increases, the airflow over the wing becomes more turbulent, creating more lift. However, if the angle of attack is too high, the wing may stall and lose lift.
3. How does the shape of the wing affect the airflow?
The shape of the wing, specifically the curvature and thickness, plays a crucial role in the aerodynamics of the wing. A thicker and more curved wing will create more lift, while a thinner and flatter wing will create less lift but allow for faster speeds.
4. What is the boundary layer and how does it impact the airflow over the wing?
The boundary layer is the thin layer of air that directly interacts with the surface of the wing. As air flows over the wing, it creates friction with the surface, which slows down the air molecules in the boundary layer. This can affect the overall airflow and lift generated by the wing.
5. How does the shape of the wing change during flight?
During flight, the shape of the wing can change through the use of flaps and slats. These are movable surfaces on the trailing edge and leading edge of the wing, respectively, that can change the curvature of the wing. This allows for adjustments in lift and drag, which are necessary for takeoff, landing, and different flight conditions.
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