2006-07-08 13:54:23 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
By aerodynamic friction i'm assuming you are talking about the net drag not specifically the skin friction drag or form drag.
Anyways, with that in mind, it wont have much impact if closed. When car manufacturers install sunroofs, they make sure it is very smooth and aerodynamic. This is likely more due to the fact that it would generate a good amount of noise (just like your side mirrors) if they didn't than anything else. (Although lower drag is always better :) )
If the sunroof is open, you will definitely have more drag due to the turbulence (as a previous answer stated) generated.
Also, a small "wind guard" thingy flips up when you open a sun roof to prevent a resonating noise. (next time you are driving on the highway, push it down, or just open your windows a little bit. The pulsing is not too pleasant).
2006-07-08 20:40:42 · answer #1 · answered by polloloco.rb67 4 · 3⤊ 1⤋
Decrease, but your engine can't get you to speeds high enough for a sunroof to have any measurable impact.
2006-07-08 21:08:54 · answer #2 · answered by wdmc 4 · 0⤊ 0⤋
if you mean friction against bodywork, yes it is reduced, but the car's drag is increased especially when it is open due turbulence and discontinuity of the trajectory of the air. when it is closed depends on the design. a smoother surface is better.
2006-07-09 01:28:10 · answer #3 · answered by PABLO Z 1 · 0⤊ 0⤋
They are actually just about neutral except when open. Then they are slightly negative.
2006-07-08 21:27:16 · answer #4 · answered by Anonymous · 0⤊ 0⤋