"Pressure contours and streamlines at α = 10 for NACA 63–021 with straight leading edge and with tubercles. a. Shows mid-chord separation line on the upper part of the conventional wing. b. Shows large vortices downstream of the troughs along the leading edge and laminar attached flow downstream of the tubercles without separation. Images source"
https://blog.gridpro.com/a-whale-of-...n-wing-design/
This is for wings, but the increased laminar flow..?
Turn the pic 90% and I can see wheels and wing mirrors etc in turbulent troughs... maybe..??
Perhaps the bottom of a car too.
More links:
https://academic.oup.com/icb/article/51/1/203/636829
https://youtu.be/dz39guNxAc4