Another great video on Original Motor Car! Drew, you asked (around 27 min) about the reason vinyl tops seemed to allow increased speed over a car with a conventional painted roof. In a nutshell, a body passing through a fluid (in this case, air) is slowed down by something called skin-friction drag. If the air passing over the car’s roof is smooth, it holds the car in a tighter grip, but if the air is turbulent, it lowers the grip and allows the car to go faster. The textured surface of the vinyl roof therefore adds energy (turbulence) to the air passing over it, and the aerodynamic drag is reduced allowing the car to go slightly faster. This is a foundation of aerodynamics, and books have been written explaining it. Next time you are on an airplane, look out the window over the wing and you will see small blades protruding near the front of the upper surface of the wings. Those are called “boundary layer fences,” and their job is to make the airflow over the wing transition from smooth (laminar) to turbulent for multiple, similar reasons. Hope this helps.
Fantastic and interesting!
Thanks, Dan! Appreciate the watch and the comment!
Another great video on Original Motor Car!
Drew, you asked (around 27 min) about the reason vinyl tops seemed to allow increased speed over a car with a conventional painted roof. In a nutshell, a body passing through a fluid (in this case, air) is slowed down by something called skin-friction drag. If the air passing over the car’s roof is smooth, it holds the car in a tighter grip, but if the air is turbulent, it lowers the grip and allows the car to go faster. The textured surface of the vinyl roof therefore adds energy (turbulence) to the air passing over it, and the aerodynamic drag is reduced allowing the car to go slightly faster. This is a foundation of aerodynamics, and books have been written explaining it. Next time you are on an airplane, look out the window over the wing and you will see small blades protruding near the front of the upper surface of the wings. Those are called “boundary layer fences,” and their job is to make the airflow over the wing transition from smooth (laminar) to turbulent for multiple, similar reasons. Hope this helps.
Very cool, and a great explanation. Thanks for the comment!
❤
Thanks!