I like sun-roofs. other people like them too. Unfortunately, laws of fluid motion state that imperfections cause turbulence. In the case of a sun-roof, the relative motion of the wind over the relative stillness of the air in the car creates a pressure difference, and sucks wind into the car. This lets the wind whistle, and get into the car, and blow around, generally wreaking havoc.

For this, many cars have a small pop-out 3 inch wide (or so) metal plate that tilts to deflect wind.

Unfortunately, at different speeds, a different angle is needed for optimal wind avoidance. Too low, and wind gets in. Too high, and whistling occurs, and wind gets in

A small wind-speed sensing chip would control the angle, as that the faster you go, the more pressure difference there would be, thus a steeper angle would be needed, thus negating the pressure difference.
-- DesertFox, Mar 31 2006

My car has this (Corolla LE), albeit without the angle control. Not even rain gets in on the highway.
-- Shz, Mar 31 2006


That's funny, my Volvo doesn't. Idea edited. Now is about angle control specifically.
-- DesertFox, Mar 31 2006



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