On Monday, September 5, 2016 at 5:20:34 PM UTC-4, wrote:
...Turbulators increase the boundary-layer thickness because they
force the thin, laminar boundary layer to transition into the thicker,
turbulent boundary layer.
Turbulators do not make the boundary layer "stickier."

Vortex generators do not make the boundary layer thinner; they alter
the boundary-layer velocity profile, making it "fuller."

Thanks Dan!
Best Regards, Dave