What a brilliant Idea!

[Ernie]

I came across this brilliant idea today and needed to share it.

http://pesn.com/2006/05/11/9500269_Engineair_Compressed-Air_Motor/

[pyrocasto]

Very interesting. Air pressure could be a good fuel, but I wonder how large of a tank, and how much pressure it would have to have, to carry you say 20-30 miles.

Glad to see someone make a decent air motor finally.  8)

[WH_Conley]

How large a compressor and power source would it have to carry for an extended trip.

[Ernie]

This is the article which originally grabbed my attention.  I suppose that at a high enough pressure in a strong enough tank, you could go quite away on a tankful.

http://www.stuff.co.nz/life-style/motoring/5903145/The-bike-that-runs-on-air

[Al_Smith]

Before ya'll get too carried away on this thing has anyone ever  seen what high pressure air can do if it gets let loose?

FWIW on the U-boats we used 4500 PSI air which was stored in air flasks external to the pressure hull for one specific reason .If they were ever to rupture or leak it could have killed the entire crew in one fell swoop .HP air is not something to toy with .

Likewise has anyone ever heard of knocking an oxegon bottle over and breaking the valve off and the tank gets propelled about a half a mile or goes right through the cab of a pick up truck ?Something to think about .

[LeeB]

Saw an O2 bottle get dropped on the stern of a supply boat once. It knocked off the top of the botlle and the last I saw of it, it was cutting a rut toward Mexico. Impressive.

[pyrocasto]

Like a scuba tank, the smaller tanks dont worry me AS MUCH, but I think you may need a pretty large tank at some serious pressure to get you anywhere with 4 wheels.

I wonder how far 100gallon lower pressure(maybe 200psi) would get ya. Way above my head on those calculations for sure.

[Brucer]

Likewise has anyone ever heard of knocking an oxegon bottle over and breaking the valve off and the tank gets propelled about a half a mile or goes right through the cab of a pick up truck ?Something to think about .

I've heard of, but not seen either of those. What I did see was a concrete block wall that a cylinder had gone through... and you could have driven the pickup through the hole

[Brucer]

In the days of steam, underground mines sometimes used compressed air engines to move ore cars in and out of the mines. The air tanks didn't have to be huge because there were compressed air hoses near any active section of the mine (to power the drills).

Off the top of my head ...
-  Stored energy = air pressure times tank volume
   Energy [ft-lbs]= pressure [PSI] x volume [cubic feet] x 144

[shelbycharger400]

Monash University in Melbourne tested an earlier dipietro motor in 2002, and provided a complete report. This is no longer published as the motor design has further advanced, based on insights gained from the independent tests.

yep... must have had too much information in that article !

i like how it says it emits NO emmissions...   hmm... yep, but how about manufacture of the materials,  machining, and the system to fill its air tanks.

also, no statement of distance of travel , or weight to test vehicle to tank.
shure i can strap a few air motors to a go cart, put my 50 gal air tank on it, it might make it across the yard... SUCcess!

[shelbycharger400]

i looked up a simmilar air motor on a search engine
A novel rotary engine has a single toroidal cylinder and a set of pistons on a rotating circular piston assembly. A rotating disk valve perpendicular to the toroid has a cutout position which periodically traverses the chamber to allow passage of a piston therethrough. The geometry of the pistons and the valve are arranged to minimize the residual volume, by altering the geometry of the chamber section formed between valve and piston and/or providing pistons which are mechanically extendible and retractable in synchronization with the opening and closing of the disk valve, to optimize engine efficiency and performance.

think of your a/c pump on your car,   its a swash plate or variable baised upon load
hmm..maybe ill put air to a compressor motor

[zopi]

Driver side air...tank...with the way boneheads drive, I really do not want anything that high pressure on wheels...

[Al_Smith]

So evidently this new design is a series of pistons that move on a swash  plate .Too bad they didn't consult with Vickers because they've made a hydraulic pump for years that works on the same principal.

[mad murdock]

So evidently this new design is a series of pistons that move on a swash  plate .Too bad they didn't consult with Vickers because they've made a hydraulic pump for years that works on the same principal.

Right Al. That style hydraulic pump has been around since before WWII in the aviation world.

[Al_Smith]

They are a specialty pump and quite costly .I've seen same on certain machine tool hydraulics .

[Grunex]

seems to me that distance is limited by the amt of compressed air, (kind of like a balloon shooting towards the ceiling).  What would impress me is if he could design that air motor so that it could use a venturi system to constantly recharge the air tank or something of that notion.  To replenish that air,  one could put an electric motor on the vehicle to pump up that air tank, but that is counter productive as well because it more than likely would require the use of batteries, and electric motor, and excess hardware, not to mention that it will add more weight. 

Maybe someone could elaborate on the idea of a venturi/turbine system to compress the air as the vehicle is moving????  would this be feasable? or do you think that a venturi would just add more drag?  what about road kill strikes? and bugs? possible hinderance?    I'd hate to be the one late to a party because I had a woodchuck stuck in my wind pipe.............lol

[Autocar]

Theres a local company here thats been working on a compressed air motor ,the way the owner explained the motor to me theres operated on a twin cylinder. He told me about the horse power it developed but I don't remember it anymore  :

[bandmiller2]

In this old world you don't get anything for nothing,likely the containment of high pressure air would be as expensive as batteries.To elaberate on what Brucer said they used to use fireless locomotives in mines.Basically a large thermos bottle charged with high pressure high temp. water from a boiler it would slowly flash to steam and run the loco for a full shift. Frank C.

[bandmiller2]

Ernie, that motorcycle gives new meaning to the term crotch rocket. Frank C.

[CTYank]

They're selling a compressed-air car in India now: http://www.popularmechanics.com/cars/news/preview-concept/4217016

Uses 4350 psi air, can be re-charged directly (seen estimates of 30 minutes) or via on-board electrical compressor in 4 hrs.

I'd pass on carrying air at that pressure, especially in India with so many unlicensed drivers.
Compressing air up to that pressure takes some very serious machinery and involves dissipating huge amounts of heat (which can't help efficiency.) And it's really powered by ... how 'bout a nasty, dirty coal-fired generating station? Nice.

[bandmiller2]

I can see the use for air power in places like mines or wherehouses where exhaust fumes are a problem,but like air tools,handy but not efficient. Frank C.

[Hilltop366]

There claim is a high efficient motor but it would also need a efficient way to produce the compressed air. not that producing and distributing gas is very efficient.

I know what your saying about air tools bandmiller, just think of what is required to continuously run a air random orbital sander, a minimum of a 5 hp compressor I would think, compared to a electric one with a very small fractional hp motor. The difference in the electricity used is huge.

[rowerwet]

i read the whole site on these cars a few years ago, they use the car motor as a pump, driven electrically to recharge the air tank while parked, plugged into the grid. the range was about 50 miles. the tanks are wound carbon fiber 3,500 psi, the same type used in airbus aircraft, if ruptured in a crash they turn into a ball of carbon fibers, rather than a torpedo.
  The air car makes sense in remote parts of India where there isn't gas or much of a grid, I believe they were planning on using a barge moored in a river with water turbines to compress the air.

[Handy Andy]

  When I worked in a cabinet shop, they had air powered random orbit sanders.  And a big air compressor.  You had to stop once in a while to let the compressor catch up.