Posted on 02/22/2005 3:21:25 PM PST by goldstategop
These are no ordinary cars. Power comes from fresh air stored in reinforced carbon-fiber tanks beneath the chassis. Air is compressed to 4,500 pounds per square inch — about 150 times the pressure of the typical car tire. The air is fed into four cylinders where it expands, driving specially designed pistons. About 25 horsepower is generated.
Though technical problems are being worked out, company officials say the car is capable of 70 mph and a 120-mile range under normal city conditions, performance that is comparable to electric cars.
Critics say the car has had trouble living up to its range projections. But company officials say they are trying to overcome that by warming the stored air.
Recharging the onboard tanks takes about four hours using the car's small compressor, which can be plugged into any wall outlet. Gas stations equipped with special air pumps can replenish the tanks in about three minutes. Company officials say the oil only needs to be changed every 31,000 miles.
(Excerpt) Read more at latimes.com ...
No more pressure than required to drive the pistons. Granted, the low end would be 35 to 40 but the high end would be 80 PSI. Then consider this, about 200 to 250 HP out of four cylinders. Todays tech and they could produce a steam car that will get in excess of 500 miles before you had to re water and put more methane/whatever for the boiler. One of the articles I had seen on the Stanley was that you came home in the winter..shut down the boiler to pilot and quik coupled it to your hot water heat in your home. So you heat your house with the car as a add on heat source. The boilers were copper coiled..need not say any more as you dont run copper with anything with high pressure. No more danger than todays gasoline engines...matter of fact I would sooner drive one than a gas engine car if one was made.
The one particular car I saw looked like a Hudson conversion and it had no brakes as the engine was the brake. About 100 moveable parts and was direct drive. Could stop and start on the steepest of hills. Took about 3 minutes to get up a head of steam to start in the morning in winter. Cruised at 60 plus MPH.
The world land speed record was held for many many years by a Stanley. 127.7 MPH at Daytona Beach in 1906 or 7.
Why did they go by the wayside? Because gasoline was 5 gallons for about 13 cents back then..thats why.
Do a google search for "Trunk Monkey" I think you will like them.
"Recharging the onboard tanks takes about four hours using the car's small compressor, which can be plugged into any wall outlet."
Seriously?!
I am really tempted to look up the energy requirements for compressing air from 0 psig (14.696 psi absolute) to 4500 psig (4514.696 psi absolute) in a Perry's Engineers Handbook, because methinks the horsepower requirements on a copressor charged with this task would be out of sight.
I have a two-stage reciprocating air compressor in the barn that takes air from atmospheric to 150 psig, and it requires a 5 hp electric motor to handle 80 gallons of air (10.7 cubic feet, 0.3 cubic meters). Granted, they're sure to be using a multistage turbine to do this, but the power requirements have got to be out of sight.
I assume France has 240V plugs everywhere? We don't here, of course, and if you've got half the voltage, you need double the amperage. If they have a 20 amp 240V outlet, we'd need a 40-amp outlet to match the net wattage. Net Energy in must equal Net Energy out (Work done to compress the fluid plus and frictional losses. My old rule of thumb used to be 72% mechanical efficiency on a turbine). Energy = Wattage*time.
I just might see if I have my handbook, just for fun.
That's what worries me...what happens to those 4500 psi tanks when you hit one of those "bumps";)
You have to run turbines with extreme high pressure steam. If you dont you dont get mush power.
Steam engines do not require high pressure.
I've seen the trunk monkey video's. They are hilarious.
MDI's website, FWIW.
http://www.theaircar.com/
Hmmm ... I don't get it ... when I html the properties using img src, nothing happens, but if I google the address, it comes up.
Anyway, I bought my first Air Hog at a Goodwill store about 7 or 8 years ago. The box advertising fascinated me ... and Whatayaknow! ... the sucker FLEW!
France has an add in the current Forbes extolling French technology. The GE EuroCEO says"The French have a passion for engineering and technology for research and solutions that push back the boundries"
The add says and I'm not making this up,"I'm a car fanatic and I can still remember when the Citroen DS was introduced in the mid 50's. It was incredibly advanced, way ahead of it's time"
Oh yes... www.thenewfrance.com is the place to go to find out more. (I didn't go)
I'll bet Steve Forbes was laughing his ass off as he deposited the check for the add.
You need to do more research. Stanleys all used pressure vessels except perhaps for the last few models. They even tried winding them with wire, but they still were prone to bursting. White used a tube boiler, as did the Doble. They couldn't explode because the secional area of a single tube was too small to explode even if it burst. The White used a coiled tube while the Doble used a vertical tube arrangement. Doble was the only one to use superheated steam at about 750 psi the rest were about 125 psi max.
This one, I know what drives the engine... from the dark days of WWI in the UK, this guy was resourceful:
"Gas Bag Car" c. 1918
This is much like the Rankin cycle engine, but it used Freon and worked much like an air conditioner in reverse. Variations on this theme are the Dyna Cam and the Wankle
It is obvious to me that Something is going to be invented.....
You are apparently unaware of multi-stage compressors. They take far less power to produce high pressure than sigle stage compressors. I daily start one electric motor which does indeed turn out the 1000 watt mercury light. It is 350 HP and starts an impeller weighing about 10 tons.
Its supposed to be charged from an electric-motor driven compressor. Electricity in France is mostly nuclear.
The whole idea is to be an alternative to electric cars, which are charged in a similar way -by plugging them in- and take even longer to charge, and to hydrogen-based fuel cells which would get their hydrogen(in whatever form) from an electric power based process.
The total energy efficiency of the thing may be lousy, but may not be relevant if you can substitute electricity from nukes for petroleum fuels.
Absolutely! (BSME UT Austin 1979)Its amazing how many hare-brained ideas are accepted before a hard headed engineer reminds them of the facts of life.
Instantaneous expansion over 300 times the volume of the tank. Bang, you will be dead.
Maybe we need to re-think this. Steam without pressure will do nothing but heat something it comes into contact with.
I thought her engineering was delightful.
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