add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
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.
I rue the day they stopped doing this
http://en.wikipedia.../wiki/Quarter_glass
and if anybody knows of a shop that will put one in a modern car (cheaply)... [FlyingToaster, Jun 26 2009]
P-51 cold air intake
https://i.pinimg.co...ustang-mustangs.jpg
[Voice, Nov 26 2021]
2CV
https://www.classic...s-guide-citroen-2cv
..... separately controlled fresh-air ventilation and warm air heating, radial tyres and hydraulic brakes were also well ahead of period rivals. Headlight beams adjustable from inside and even road-speed-related wipers (driven from the speedo cable) took Deux Chevaux innovation well into the future. [xenzag, Nov 27 2021]
[link]
|
| |
They're not bullet holes, they're ~speed~ holes. |
|
| |
your car has AC but not vents and a fan? |
|
| |
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! |
|
| |
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 |
|
| |
I think my mic is off again... |
|
| |
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 ... |
|
| |
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... |
|
| |
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 ... |
|
| |
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. |
|
| |
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). |
|
| |
So, the terracota army was for an Invasion, the
water was in the pots.invasion scrapped and
lost by a naff quartermaster.... |
|
| |
Baked on all Citroen 2CVs which have a simple flap
controlled vent running along the front of the car
under the windscreen. Wire mesh prevents larger
particles like bluebottles from flying in. These cars
were and are decades ahead of any of the high
tech chip controlled rubbish produced today. |
|
| |
//Look at the radiator air intake on a P-51 fighter airplane
for an illustration. (that scoop on the belly on the plane).// |
|
| |
There's quite a bit going on with the P-51 cooling solution.
The important part is to have the intake be as small as
possible in terms of frontal cross-sectional area, that keeps
your drag low. To make such a small inlet work, you have to
figure out how to make it work. The inlet faced relatively
high pressure air (prop wash) so they gently ducted it to a
very large radiator* in a large volume. The key was control
of the exit, by continuously changing the outlet flap, which
was almost always more than the inlet. |
|
| |
//These cars were and are decades ahead of any of the
high tech chip controlled rubbish produced today// |
|
| |
While I love the 2CV, I've also driven one and it's not a car
by modern standards. It's dangerously slow, fuel inefficient
and almost certainly lethal in many crashes. Opening a flap
to let in air works just fine, unless you need some control
of the quality of that air, in older cars, the engine gets air
filtration, but not the cabin for some reason. |
|
| |
Don't blame car manufacturers for the nature of modern
cars. Car manufacturers were super happy re-hashing the
same platform for decades. It's regulations that have
changed the nature of cars. If you want to design a car
nowadays, it's so constrained by the sum of global
regulations that it's no wonder they all look more or less
the same. |
|
| |
Personally, I think cars peaked around 1994. The
opportunities of technology were being realized, but
without too much intervention. |
|
| |
*radiators aren't really radiators, water-air heat
exchangers, but anyway. |
|
| |