[euromodder]

Would it be beneficial from an aerodynamic point of view, to keep the airflow that's going over the windshield and roof, on the windshield and the roof by using some longitudinal fences - say 0.2 to 0.5 inch high to trap only the boundary layer - to prevent it from spilling over to the sides ?

I have a Volvo V50 station wagon with rather squarish corners along the sides of the roofline.

When using the windshield washers, a lot of the fluid spills over the top half of the side windows, obviously by turbulent air - annoying, but also illustrating the aerodynamic effect of the mirrors.

Keeping the washer fluid from the side windows is what sparkled this idea, but why not extend it all the way to the rear ...

Ideas ?