In my poor third world country, gas prices are a big drain on the pocket.
If you drive without air conditioning, you should save maybe 10% in fuel. But if your commute involves a long stretch of fast highway then the air resistance of open windows will cut into your fuel savings. In my country, its usually too hot to drive with the windows closed.
Specially with my car, i have to roll down the windows say 50% for enough air to hit me. a lot of air goes past me into the rear passenger area. If i just roll down the windows 2-3 cm and add a device which more efficiently redirects the air from outside onto me then i can decrease aerodynamic drag. I'm thinking of a series of flaps which redirect the air rushing past the window towards me.-- vmaldia, Jun 26 2009 I rue the day they stopped doing this http://en.wikipedia.../wiki/Quarter_glassand if anybody knows of a shop that will put one in a modern car (cheaply)... [FlyingToaster, Jun 26 2009] The flip down visor works wonders for this purpose.-- 21 Quest, Jun 26 2009 They're not bullet holes, they're ~speed~ holes.-- BunsenHoneydew, Jun 27 2009 your car has AC but not vents and a fan?-- WcW, Jun 27 2009 Can you spell hand?
More seriously why not have a terracota, or suitably porous water container, that fits into the gap of your 5cm wound down window? Have holes, directed at you through the ceramic. That will be chilled air!-- 4whom, Jun 27 2009 Perhaps you could adapt the Indian airconditioning system from backpacker hostels I stayed in long ago - hessian strips are soaked in water and hung across the window. The air evaporates the water on its way through.
It worked really well - but may impede driver visibility though-- kindachewy, Jun 27 2009 I think my mic is off again...-- 4whom, Jun 27 2009 Oops - yes I guess 'suitably porous water containe' could be hessian strips. Seemed different enough from the terracotta though to be worth a mention
Like I say, it's a great (and very cheap) aircon system ...-- kindachewy, Jun 27 2009 Interstingly our (RSA) water canteens were made from several layers of a thick weave (hessian-like) wrapping a completly porous stainless steel container (more like a seive really). That water was pure heaven. Not that I was in the army, but I did sup from my Dad's army canteen, which was standard issue at the time...-- 4whom, Jun 27 2009 How much water do you lose with that design? Probably not the best one to use if you're planning to make it out of the Namib ...-- kindachewy, Jun 27 2009 You lose plenty water, the Angolan forces (up there in the Namib) were given a funny plastic job. A bit like a hot water bottle that you could drive an A1 Abrams over, without damage.-- 4whom, Jun 27 2009 The two big differences I note with modern cars versus 1960s and 1970s models is 1) as Vmaldia notes, the minimal air flow when a window is cracked open and 2) the pulsing air pressure of about 1 hertz that establishes when you have only one window open at speed.
I'd suggest an insert between the door frame and the window, about 8 cm / 3" wide. Mostly, it would be an extension on the window. But in front of the drivers / passengers position, it would have an air scoop to an adjustable, steerable inside air vent. Like the ones on 2-4-seat aircraft. They'd blow a LOT of air, but add drag over a small surface area (25 cm^2, 4 in^2). I've seen inserts somewhat like that for two different purposes: 1) to accomodate a curved plexiglass air dam of sorts of dubious aerodynamic worth and 2) to mount a PV-powered fan in a back-seat window to provide positive ventilation while parked in the sun.
I still remember a 1967 Plymouth Valiant that had an air box outboard of your shin (driver and passanger). When you opened it up at 100 kph, there was a HUGE wind blowing up your legs and hence onto your upper body. The air intake pointed forward and there was large diameter duct all the way to the air box. It had the effect of dropping the effective temp in the car about 10C/18F. So, yes, your idea would work.
Look at the radiator air intake on a P-51 fighter airplane for an illustration. (that scoop on the belly on the plane).-- DavidinKenai, Jun 29 2009 //2) the pulsing air pressure of about 1 hertz that establishes when you have only one window open at speed//
Thanks for the memory. What a crappy reason for eliminating the quarter light.-- bigsleep, Jun 29 2009 halfbakery