I am mounting solar panels on top of a recreational vehicle (RV). To reduce drag, I was planning on building a small ramp in front of the panels to deflect wind before it hits the flat panel and mounts. Here is a rough sketch (red is brackets, black is panel, purple is ramp):
Someone told me that there would be MORE drag if I did it this way than if I didn't put the deflector/ramp. I will do the work even if there will be VERY LITTLE difference between drag avoided by putting in a ramp and not having a ramp at all, but I definitely don't want to do it if it will INCREASE drag.
I think the space under the panel will be minimal. I am going to try to get them as close as possible to the roof. The panels are about 2" thick and the space between will be roughly 1/4-1/2 inch.
How would adding a ramp in front of the panel affect drag on the vehicle? Would it increase, decrease or stay the same?