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I came across this question while studying stalling of airfoils. How does the chord length of an airfoil affect the position of the separation point of flow?

https://en.wikipedia.org/wiki/Flow_separation

The Wikipedia article on flow separation isn't very clear on what is the relation between location of separation point and Reynolds Number (and thus Chord Length).

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    $\begingroup$ Could you please link to the question? Without a link it is hard to know what you refer to. If you are unsure about linking: Click on edit, highlight the text and then call up the link dialog by clicking on the chain symbol on the bar above the edit box. Enter the link there and save. $\endgroup$ Apr 6, 2016 at 7:12
  • $\begingroup$ @JayMetha, it appears you edited the question, but didn't do it from the same account or browser, so the edit needs to be approved. Please, try to consolidate your identity (I am sure it is described somewhere in help). $\endgroup$
    – Jan Hudec
    Apr 6, 2016 at 9:18
  • $\begingroup$ @JanHudec I submitted the question as a new user on my browser and edited on the iOS application. I'll post the question again with the edit as I can't find a solution to the problem $\endgroup$
    – Jay Mehta
    Apr 6, 2016 at 9:41
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    $\begingroup$ @JayMehta, absolutely don't post the question again. $\endgroup$
    – Jan Hudec
    Apr 6, 2016 at 11:37

1 Answer 1

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The chord length is a minor influence. The main driver for separation is the local pressure gradient.

Make sure to read the first three paragraphs of this answer if you are unsure how the pressure gradient drives separation.

The chord length only comes into play via the local Reynolds number. Higher Reynolds numbers mean steeper pressure gradients can be tolerated, but the effect is rather weak. It shows in the separation point which moves back slightly on the upper side of an airfoil near stall at the same angle of attack when the Reynolds number is increased.

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