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As far as I know leading-edge dynamic stall is characterized by the formation of a Leading edge vortex. This leading edge vortex forms due to the 'bursting' of the LSB (Laminar separation bubble). However, if the airfoil is tripped on the upper surface to make the boundary layer fully turbulent, does that suppress the leading edge vortex? if so, what will be the process leading to the dynamic stall in this case?
Your help is greatly appreciated.
if the airfoil is tripped on the upper surface to make the boundary layer fully turbulent, does that suppress the √leading edge vortex?
I would say no, because supercritical wings that have that LSB problem, and so suffer from leading edge stall, aren't improved by leading edge contamination, like frost coatings or heavy bug accumulations, which can be presumed to destroying laminar flow well forward of the normal transition point.
On the CRJ200, which has a particularly nasty unrecoverable LE stall due to LSB formation at the leading edge, contamination only serves to reduce the stalling AOA to below shaker/pusher onset, without making the stall any more benign, as a number of frost contamination crashes have shown. The bubble is still there even with the rough surface forward of it, and so the wing still lets go all at once, just at 9 degrees instead of 15.
The LSB formation is particularly bad on supercritical wings because the profile has an odd kind of "corner" or discontinuity in the curvature because of the extra thickness forward, which gives a kind of squared off profile at the LE.
