Hello,

I was reading a paper which describes the evolution of leading/trailing edge vortex (L/TEV) of an airfoil. The author wrote that

"The LEV remain attached to the airfoil until the end of the stroke, after which it is shed. After that, the LEV still remain on the surface of the airfoil and require half a period to move to the trailing edge of the airfoil."

I thought when a vortex is shed, that means it is detached from the airfoil surface. When does the author say that it still remains on the airfoil? Does this contradict the definition of "shed"?

Thanks

It is in close proximity to the airfoil upper surface and has a pronounced impact on the airfoil pressure distribution.