Boundary vs. Flow Separation

[JTC]

Could someone please go here...

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

And explain to me the difference between Flow and Boundary Separation discussed in the opening.

Because this explanation makes no sense to me. I have the problem. I just don't understand the difference.

 

[Lord Jestocost]

I don’t think that there is a difference. In Paul K. Chang’s book "Separation of Flow“ one reads in chapter I: "The classical concept of flow separation is because of viscosity; therefore, it is often expressed as boundary layer flow separation or boundary layer separation.“

 

[boneh3ad]

Boy that Wikipedia intro is a mess. There's no difference, and their description of what it is ("speed of the boundary layer relative to the object falls almost to zero") is utter nonsense.