the perfect car for politicians

[daniel49]

Text

One benefit of these high prices are that everyone and his brother seem to be trying to come up with the next big energy idea.
In a Few years maybe we can sort out the practical from the impractical, in the meantime pelosi needs to realize we still need fossil fuels for the transition.

 

[frostedflakes]

Sounds pretty interesting, but as the article points, you'd need one hell of a compressor to achieve such high pressure. Those cheap 1HP compressors you can pick up at hardware stores only do about 125PSI. High-pressure industrial compressors cost thousands of dollars.

I also doubt wall-to-wheel efficiency of these cars could match that of plug-in electric vehicles. The range they claim is pretty amazing, though, definitely better than current electric vehicles in that area.

 

[dmcowen674]

As much as I like anything that gets us less dependeant on oil we can't make oxygen tanks that won't explode, imagine these?

 

[StageLeft]

Borders on irresponsible. Another fantasy vehicle. I am surprised it wasn't a link to the moller sky "car". Air-powered car as soon as they say working like this at those prices? Complete fantasy.

As much as I like anything that gets us less dependeant on oil we can't make oxygen tanks that won't explode, imagine these?

For the rubbish in this article the tank would be under OBSCENE pressures.

 

[conehead433]

Originally posted by: dmcowen674
As much as I like anything that gets us less dependeant on oil we can't make oxygen tanks that won't explode, imagine these?

I'm pretty sure they're filled with air and not oxygen.

 

[herm0016]

only a basic understanding of physics is needed to understand this is a sham

 

[Mark R]

The tanks do worry me a bit - the pressures discussed are significantly higher than even the highest pressure SCUBA equipment, or normal pressurised gas tanks. Failure of one of those tanks would be quite spectacular.

The range claim is also a bit misleading, as it's a 'presumed' range. Although protoype cars and compressors have been built for demonstration purposes, they've only been equipped with conventional steel tanks operating at much lower pressures. The quoted range is therefore based on extrapolation from test results to high pressure tanks (which haven't been tested) as well as correction of a few design problems with the prototype engines, and the use of improved tire technology.

 

[daniel49]

guess I should supply the link to the video that was in the article for the skimming readers.

video


edit: and heres some more pics from mdi website
Text
I'll wait till i see the six seater sedan before i judge.:camera:

 

[RY62]

Now this is something I's like to see.

I've got a 6000 psi, four stage, breathing air compressor with extra storage tanks in my shop. I'd already have my own fueling station.

 

[Toastedlightly]

Originally posted by: dmcowen674
As much as I like anything that gets us less dependeant on oil we can't make oxygen tanks that won't explode, imagine these?

We can make tanks that don't explode. Carbon fiber tanks are lighter, and instead of having cracks propogate in all directions, carbon fiber can be manufactured to have a crack split in one direction. In effect, a side of the tank "splits" open, venting all the compressed gas and not causing shrapnel to fly in all directions.

 

[CycloWizard]

Even industrial compressors are designed to achieve a 4:1 maximum compression ratio. Anyone who has taken sophomore-level engineering courses knows this. The common solution when higher pressures are needed is to string compressors together in series. Assuming that this could be done without significant difficulty (which I sincerely doubt), water from the air would still condense out and damage the compressors. Of course, this could also be overcome by adding driers to the line, but they would have to be changed frequently and add considerable technical obstacles to the already ridiculous compressor system. In other words, I'll believe it when I see it.

 

[OokiiNeko]

Air power info

Apparently at least one air car has been built already.

 

[CycloWizard]

Originally posted by: OokiiNeko
Air power info

Apparently at least one air car has been built already.

No one is doubting that it can be done. We just doubt that it can be done to the specifications described by this company.

 

[RY62]

Originally posted by: CycloWizard
Even industrial compressors are designed to achieve a 4:1 maximum compression ratio. Anyone who has taken sophomore-level engineering courses knows this. The common solution when higher pressures are needed is to string compressors together in series. Assuming that this could be done without significant difficulty (which I sincerely doubt), water from the air would still condense out and damage the compressors. Of course, this could also be overcome by adding driers to the line, but they would have to be changed frequently and add considerable technical obstacles to the already ridiculous compressor system. In other words, I'll believe it when I see it.

Industrial air compressors, dryers, and filtration are things I happen to know a little about.

The problems you point out were overcome long ago by using multi-stage air compressors. A single reciprocating pump with multiple pistons of decreasing size (stages).

Filtered air is compressed to low pressure in the first stage cylinder then passed through an intercooler line to the second stage clylinder. The second stage, being a smaller cylinder, compresses the air to a higher pressure and passes it to the third stage. Using a four stage pump you can easily achieve pressures of 5000 - 6000 psi. Delivery CFM vaies based on horsepower of the drive motor, bore and stroke of the cylinders, and RPM of the pump.

Compression of the air generates heat. Heat is removed by air or water cooling as the air passes through the inter-stage coolers and after final compression with an aftercooler. The cooling process causes moisture (humidity in the intake air) to condense to liquid. High pressure membrane dryers can be used between stages (up to 1200 psi) for moisture removal. As there is significant heat in the pump, the condensation primarily occurs after final compression and cooling causing water to condense in the compressor storage tanks. The tanks are equipped with drain valves to remove the liquid.

Compressed air from the storage tanks is typically passed through a coalescing (oil removal) filter to a desiccant dryer which drys the air to a - 40f dewpoint and finally through a fine particulate filter. An activated carbon filter can be added to the mix for breathing air or lab quality air. The compressed, dried and filtered air is now ready to use in the air car.

A setup like this, though quite common, is not inexpensive but there's no reason I can think of that these types of compressors couldn't be setup in fueling stations where the compressed air could be metered and sold for much less that gasoline. The fueling cost would need to cover purchase and maintenance of the euipment, power cost to operate it, along with a small profit.

 

[Moonbeam]

I like this design.

 

[dmcowen674]

Originally posted by: Toastedlightly

Originally posted by: dmcowen674
As much as I like anything that gets us less dependeant on oil we can't make oxygen tanks that won't explode, imagine these?

We can make tanks that don't explode. Carbon fiber tanks are lighter, and instead of having cracks propogate in all directions, carbon fiber can be manufactured to have a crack split in one direction. In effect, a side of the tank "splits" open, venting all the compressed gas and not causing shrapnel to fly in all directions.

I see, a safe explosion

 

[daniel49]

Originally posted by: RY62

Originally posted by: CycloWizard
Even industrial compressors are designed to achieve a 4:1 maximum compression ratio. Anyone who has taken sophomore-level engineering courses knows this. The common solution when higher pressures are needed is to string compressors together in series. Assuming that this could be done without significant difficulty (which I sincerely doubt), water from the air would still condense out and damage the compressors. Of course, this could also be overcome by adding driers to the line, but they would have to be changed frequently and add considerable technical obstacles to the already ridiculous compressor system. In other words, I'll believe it when I see it.

Industrial air compressors, dryers, and filtration are things I happen to know a little about.

The problems you point out were overcome long ago by using multi-stage air compressors. A single reciprocating pump with multiple pistons of decreasing size (stages).

Filtered air is compressed to low pressure in the first stage cylinder then passed through an intercooler line to the second stage clylinder. The second stage, being a smaller cylinder, compresses the air to a higher pressure and passes it to the third stage. Using a four stage pump you can easily achieve pressures of 5000 - 6000 psi. Delivery CFM vaies based on horsepower of the drive motor, bore and stroke of the cylinders, and RPM of the pump.

Compression of the air generates heat. Heat is removed by air or water cooling as the air passes through the inter-stage coolers and after final compression with an aftercooler. The cooling process causes moisture (humidity in the intake air) to condense to liquid. High pressure membrane dryers can be used between stages (up to 1200 psi) for moisture removal. As there is significant heat in the pump, the condensation primarily occurs after final compression and cooling causing water to condense in the compressor storage tanks. The tanks are equipped with drain valves to remove the liquid.

Compressed air from the storage tanks is typically passed through a coalescing (oil removal) filter to a desiccant dryer which drys the air to a - 40f dewpoint and finally through a fine particulate filter. An activated carbon filter can be added to the mix for breathing air or lab quality air. The compressed, dried and filtered air is now ready to use in the air car.

A setup like this, though quite common, is not inexpensive but there's no reason I can think of that these types of compressors couldn't be setup in fueling stations where the compressed air could be metered and sold for much less that gasoline. The fueling cost would need to cover purchase and maintenance of the euipment, power cost to operate it, along with a small profit.

thx for your insight to the thread.

 

[MadRat]

Originally posted by: herm0016
only a basic understanding of physics is needed to understand this is a sham

Hydraulics are better energy storage per pound than batteries. Where's the sham?

 

[StageLeft]

Originally posted by: Toastedlightly

Originally posted by: dmcowen674
As much as I like anything that gets us less dependeant on oil we can't make oxygen tanks that won't explode, imagine these?

We can make tanks that don't explode. Carbon fiber tanks are lighter, and instead of having cracks propogate in all directions, carbon fiber can be manufactured to have a crack split in one direction. In effect, a side of the tank "splits" open, venting all the compressed gas and not causing shrapnel to fly in all directions.

That sounds still like a damn good party. I would love to have a tank with the energy to propel me many miles "vent" in my trunk while I'm driving along, that would be awesome.

 

[Genx87]

Well if this is turely a car for politicians. It's claim of 100mpg will be more like 10mpg and it will demand we pay more if we want 12 mpg.

 

[RY62]

The Air Car will follow the same safety rules and regulations of all approved cars driven in the Unites States. The car?s tubular body provides increased resistance in the event of a crash. The air tank(s), located under the floor, is carbon fiber with a thermoplastic lining. If damaged upon impact, it cracks and the air simply escapes without any explosion, as there is no metal. Aerospace giant Air Bus industries will manufacture the tanks for MDI.

Vehicle Specifications
Length - 13.4 ft
Width - 5.97 ft
Height - 5.74 ft
Seating - 6 seats
Trunk volume - 35 cubic ft
Weight - 1874 lbs
Engine - 6 Cyl.
Power - 75 hp
Max Speed - 96 mph*
Mileage - 106 mpg*
Range - 848 miles (8 gal tank) *
Co2 - 0.141 lbs/mile (at speeds >35mph; zero emissions at <35mph)

* estimated performance and subject to change

Standard Features will include:

Computer based screen display of vehicle control parameters
Full CFC-free A/C
Airbags
Fully reclining driver?s seat
Power windows, door locks and mirrors
Deluxe AM/FM stereo with cassette and cd player, optional GPS
Rear window defogger
Concealed spare tire
All season 13-inch radial tires
A cold weather package will be available

Engine and Transmission Characteristics include:

Horsepower: 75
Power source: Electronically injected compressed air
Oil volume and oil change interval: 0.8 liter at 50,000 miles
Engine mount: Rear
Transmission: Automatic, Continually Variable Transmission. Rear wheel drive.
Suspension: Front coil spring, rear pneumatic.
Steering mechanism: Rack and pinion.
Chassis and body materials: Aluminum and fiber glass.
Tanks: Thermoplastic lining and carbon fiber.

Fuel Characteristics:

Compressed Air: 3200 ft3 @ 4500 psi
Charger: On board 5.5 kwh 110/220 v compressor generating 812 ft3 /hr.

http://zeropollutionmotors.us/

I don't know...this really looks like something that could work. There's a good bit of information at the website. I'm sure there'll be some challenges but I don't think there's any issues we can't overcome.

I can understand the concerns about the high pressure tanks. I wouldn't want to be strapped on top of an air tank that's pressurized to 4500 psi if it exploded but, then again, I wouldn't want to be sitting on top of 20 gallons of gas if it exploded.

Looks like they've got an on board air compressor in the specs. With that, you can plug it in over night to refill the tank. Fuel stations would still need high pressure air fueling to refill long distance drivers, cars that run out while driving, or if the onboard compressor fails.

I'd like to see more specs on the air consumption. Air is stored at 4500 psi. I wonder what regulated pressure and volume is required to accelerate the vehicle from a stop and what is required for normal driving. Would a little tweaking of the pressure and flow rate turn it into a short distance speedster?

 

[CycloWizard]

Originally posted by: RY62
Industrial air compressors, dryers, and filtration are things I happen to know a little about.

The problems you point out were overcome long ago by using multi-stage air compressors. A single reciprocating pump with multiple pistons of decreasing size (stages).

Filtered air is compressed to low pressure in the first stage cylinder then passed through an intercooler line to the second stage clylinder. The second stage, being a smaller cylinder, compresses the air to a higher pressure and passes it to the third stage. Using a four stage pump you can easily achieve pressures of 5000 - 6000 psi. Delivery CFM vaies based on horsepower of the drive motor, bore and stroke of the cylinders, and RPM of the pump.

Compression of the air generates heat. Heat is removed by air or water cooling as the air passes through the inter-stage coolers and after final compression with an aftercooler. The cooling process causes moisture (humidity in the intake air) to condense to liquid. High pressure membrane dryers can be used between stages (up to 1200 psi) for moisture removal. As there is significant heat in the pump, the condensation primarily occurs after final compression and cooling causing water to condense in the compressor storage tanks. The tanks are equipped with drain valves to remove the liquid.

Compressed air from the storage tanks is typically passed through a coalescing (oil removal) filter to a desiccant dryer which drys the air to a - 40f dewpoint and finally through a fine particulate filter. An activated carbon filter can be added to the mix for breathing air or lab quality air. The compressed, dried and filtered air is now ready to use in the air car.

A setup like this, though quite common, is not inexpensive but there's no reason I can think of that these types of compressors couldn't be setup in fueling stations where the compressed air could be metered and sold for much less that gasoline. The fueling cost would need to cover purchase and maintenance of the euipment, power cost to operate it, along with a small profit.

Yeah, I was thinking of having compressors on the car itself. Apparently my literacy is struggling this week.

edit: No, apparently my literacy was fine.

Vencat said an on-board compressor would refill the air tank while the car is running, or owners could refill it by plugging it into a power outlet for four hours.

So, I agree that it could be used at fueling stations and such, but not on the car for the reasons I mentioned previously.

 

[RY62]

Originally posted by: MadRat

Originally posted by: herm0016
only a basic understanding of physics is needed to understand this is a sham

Hydraulics are better energy storage per pound than batteries. Where's the sham?

Are they using hydraulics anywhere on this car? It looks all pneumatic to me.

I suspect herm0016 is calling it a sham because part of the design allows the motor to refill the tank(s), giving the impression of a perpetual motion machine. The refilling looks like it only happens under certain highway driving conditions to improve range.

I think this is an exciting concept that's well worth consideration. When running on air only, the emmisions will be air that is cleaner than the air that went in due to intake filtration. Even when running the air heater for improved efficiency, the amount of dirty exhaust is way lower than any combustion car we have today. Then, there's the thought of using solar, wind, or other alternatives to provide the electricity to run the air compressor.