Car that runs on compressed air is the car of the future!!

Well, I can agree with your statement that it is a cool idea and I mean that on the physical side either. A compressed air engine (CAE) runs cooler (colder even) than an internal combustion engine (ICE).

There's still the argument that it costs much more to compress the air than to use it. If I had such a car, and I had a compressor in the house for it, how much in electricity will I pay to run the compressor. Will it be more than what I pay for gasoline now? This question has yet to be answered and, for some reason, no one has made a study, as far as I know.

Then, there's the problem of present infrastructure, specifically, places where they have electrical outlets that meter how much electricity you consumed to "tank up". This is easy to implement, but there are none at the moment. In some countries, you're not allowed to "sell" or "resell" electricity.

Well, I can agree with your statement that it is a cool idea and I mean that on the physical side either. A compressed air engine (CAE) runs cooler (colder even) than an internal combustion engine (ICE). There's still the argument that it costs much more to compress the air than to use it. If I had such a car, and I had a compressor in the house for it, how much in electricity will I pay to run the compressor. Will it be more than what I pay for gasoline now? This question has yet to be answered and, for some reason, no one has made a study, as far as I know.

That's the whole beauty of this engine it really shows up the old IC piston engine in a bad light. We know that the IC piston engine has an efficiency of only about 20% right ? The steam turbine at the power station that generates the electrical power we use at home has an efficiency nearing 90%, so naturally running on compressed air, or at least filling up on compressed air is much cheaper than filling up on gasoline. Second point, if we take the power from the electrical outlet at home, that power is coming from a centralized source, it is therefore possible to monitor the whole operation closely, making it possible to release less pollutants into the atmosphere. Now, think of it in practical terms, suppose you are getting 10km/litre with your IC piston engine, you will with 90% efficiency get 90km/litre from the compressed air engine, quite a significant difference isn't it. What is comes down to is that if you pay 500 dollars to go a certain distance using gasoline, by filling up with compressed air you have to pay only 80 dollars because of the difference in efficiency between the steam turbine and the IC piston engine..

Then, there's the problem of present infrastructure, specifically, places where they have electrical outlets that meter how much electricity you consumed to "tank up". This is easy to implement, but there are none at the moment. In some countries, you're not allowed to "sell" or "resell" electricity.

Surely a lot easier, child's play in fact as opposed to setting up hydrogen filling stations?

10km/litre with your IC piston engine

90km/litre from the compressed air engine

I wouldn't know if a liter of gasoline is equivalent to a liter of compressed air in terms of energy capacity. My car's gas tank is small enough to make it comfortable. A compressed air tank (did you say 320 liters?), would take so much space that there'd be space enough for me and one passenger only. Furthermore, the weight of that tank will make up a large percentage of the total weight of the vehicle.

Also, the steam turbine is not the one producing electricity. The generator will have its own losses plus the transmission losses of the electricity to my home means that the 90% has gone even lower.

I'm all for a compressed air car once it becomes viable. I just don't think it is now.

I wouldn't know if a liter of gasoline is equivalent to a liter of compressed air in terms of energy capacity. My car's gas tank is small enough to make it comfortable. A compressed air tank (did you say 320 liters?), would take so much space that there'd be space enough for me and one passenger only. Furthermore, the weight of that tank will make up a large percentage of the total weight of the vehicle.

I have made these glowing statements in favour of the compressed air car on the premise that a pressure of 500 psi, (which is approx. the pressure after combustion in an IC engine) will perform the same amount of work regardless of the source. I.e., regardless whether the pressure is due to the combustion of fuel OR if it supplied from a tank. IF this premise is wrong then of course the whole thing falls apart. A 320 litre tank is not all that large about 1m x 1m x 0.32 m (or 3.25ft x 3.25ft x 1 ft.) So it is not in fact very large, in fact it should be possible to have two tanks, one tank will last for 7-8 hours (minimum) and when this is being used the other could be filed so that the car will always have fuel for power.

Also, the steam turbine is not the one producing electricity. The generator will have its own losses plus the transmission losses of the electricity to my home means that the 90% has gone even lower.

I agree with this, but it will still, even after all these losses work out cheaper!

I'm all for a compressed air car once it becomes viable. I just don't think it is now

The web-site says that the cars should be on the road next year I.e., 2008.

if you want a 4000 PSI tank, run the hoop stress calculation and see what the wall thickness is, and the weight of the empty tank...

If we are going to compare efficiencies we must do it in an apple to apple style. Your 20% versus 90% numbers are not comparing the methods at the same point in the generation to use sequence.

If they can have tire air pumps, why not a larger compressor?

...you may have missed the point as your post was not fully clear, please elaborate asap. Thanks.

The program I watched yesterday about these "air" cars said it cost about $2.00 to charge the car at "home", wherever that was. There were two cars featured: one in France and one in Australia. The French car had a piston driven engine, the other a rotary turbine. Both recharged the compressed air for "pennies" compared to the cost of gas to take the vehicles the same distance.

If I show you a video of me flying without any device aiding me then I take it you will believe that I have learned how to levitate?

Come on people! Scammers will tell you anything. Do you believe it just because you want it to be true? Use your brain and think for yourself. You are just taking what is being said as being true because they say it is.

On the program I saw on the Discovery Channel, the cost for the car being developed in France was equivanent to about $2.00 US to charge the tanks and it was good for about 200 miles. if I remember the miles correctly.

If you look at the energy involved, that is just ludicras. Have you noticed that everything you see on television isn't necessarily as represented? Often they only repeat what they are told. Garbage in, garbage out. Just look at the political arena. Often they don't check their facts they just get all giddy and run with it.

Maybe. The builder said it takes two hours to charge. Actually, I was more impressed with the vehicle being developed in Australia. It worked on a turbine principle with few moving parts. The models were being used in a warehouse to move heavy pallets and stuff. The way it was explained, it appears to be more efficient than the French one. I am by no means an expert on energy efficiency versus cost to produce fuel, but these vehicles seem to be something to explore.

Well among the people who actually use compressed air, there is little disagreement. It is horribly inefficient, this is an incontrovertible fact. It is only used when the few advantages it offers are of great value. Some people have covered it quite well in this thread. Chances are anyone who thinks it is a good idea has no real world experience using it and is simply accepting what they are being told because it is made to sound good. Or they are the people who want you to invest in it or have themselves foolishly done so.

I read the article and in it no where did i read any information on mpg. Using gasoline as a fuel source to compress the air. As read it we are to run to the suburbs to pollute the air there so we can run in the city emissions free on compressed air. I wonder what the cost of a compressor will be to fill the tanks to 330 bar, pricey i bet. The increase in electricity use to compress air at home will cause more pollution from the utility company's if the tanks are filled at home. As i see it it just a attempt to move the pollution around.

I have seen the damage an oxygen tank can do when it fell over and sheared the valve off. Went through two concrete block walls. I wonder how fast and how far 320 litre of compressed air at 330 bar will propel a 1000 lb projectile the car.

The vehicles were very light a gas engine on such a vehicle may preform as well.

The increase in electricity use to compress air at home will cause more pollution from the utility company's if the tanks are filled at home. As i see it it just a attempt to move the pollution around.

But still better than having the pollution coming from cars. Here the whole thing is centralized and possibly more stringent pollution requirements can be implemented.

I have seen the damage an oxygen tank can do when it fell over and sheared the valve off. Went through two concrete block walls. I wonder how fast and how far 320 litre of compressed air at 330 bar will propel a 1000 lb projectile the car.

That does seem to be the biggest concern right now. If they could put a video on the site showing what happens when a tank is punctures it might do the trick.

OK, this thing will never be economically viable, but it can still be made in the same way you can make a platinum rolling pin that will never corrode and that you clean by heating it white hot and quenching in water.

First, the compression stage is a heat engine. of sorts. You use mechanical energy to make hot air. Then you waste the heat and store the compressed air. You them use this compressed air to run a heat engine between room temperature and the high pressure and some low temperature and ambient pressure.

Two mechanisms in sequence that are at best each 25% efficient with the assorted heat losses to ambient and the low temperature differential, etc. Over all about 15% I would estimate. You would need a total energy balance ti get it right.

Run the compressor and see how long it takes an "X" horsepower motor to make "Y" cubic feet of air at 'Z' PSI. Then see what is needed to drive the car until 'Z' goes to zero, via a dynamometer setup.

From this you can get the overall efficiency.

Sure it will work, but it will not beat gasoline as compressed air has .1 % of the energy of the same volume of gasoline. Yes point one %, maybe less.

compressed air is little better than a spring operated car...we know how many there are of those made in detroit...

Thanks aurizon. I was just going to say that this is a ridiculous idea that should die and that anyone who has so little knowledge of how things work so as to think that it has any merit should probably switch over to one of the free energy sites.

But your comment takes the time to break it down in terms that are basically incontrovertible if the terms are understood or believed.

I only wish facts held sway in the face of denial. Sadly, I'm sure there will be argument.

If you have a free/cheap source of energy to compress the air, then it would be a great idea, but using the national electrical grid will NOT be a good idea at all......it has been proved that the OVERALL efficiency using electrical power or any other form of power (that needs to be paid for) to compress the air is not economical.

There have actually been steam locomotives (specially adapted to run on air) for plants where heat is not allowed or would be dangerous, I forget which and where....sorry.

Some of these locomotives are the best part of 100 years old if I remember correctly....so this car is not really a new idea.....

I do not run around with diving bottles in my car, I certainly do not want air at that pressure in my car either, forgetting the weight and size for a moment of the bottle(s)....I would rather have LPG or similar, its far, far safer.....

I have worked with 4000 PSI air on RN warships gun system Recuperators. Sealing was a problem and it is inherently dangerous, a real killer......like having 10 sticks of dynamite to work near.....only normal Oxygen bottles would I consider to be more dangerous than air at that pressure in that quantity......thanks but no thanks.....

Lets forget about efficiency for a moment and consider another reason why this idea will never pan out. The cost of compressed air from electricity is only one part of the cost. Honestly, how long do you think it would take the governments of this world to start putting extremely high taxes on any compressed air (or electrical) energy used to run automobiles on compressed air, especially as they could no longer collect gasoline or fuel oil taxes for the automobiles. (Maybe 3 millisecs). The posting suggests great cost savings, but governments would lose their tax base and that will never happen.

<There have actually been steam locomotives (specially adapted to run on air) for plants where heat is not allowed or would be dangerous>

Ah, yes! http://en.wikipedia.org/wiki/Fireless_locomotives

Though some have been developed for use on compressed air, most have a highly-insulated steam reservoir that is charged at intervals from stationary steam plant. Some interesting specimens survive, though their usefulness in the context of a heritage railway operation is very low.

Even better,the Mekarski Tram,

A problem with compressed-air propulsion is that the air cools as it expands, which can lead to the formation of ice in the power cylinders.

Mekarski sought to overcome this problem by heating the air with steam, produced in a small boiler called a bouillotte. It is uncertain whether the steam was mixed with the air, or whether there was a heat exchanger.

The system was tested in Paris in 1876 and introduced to the tramways of Nantes in 1880. It seems to have been a success at Nantes. The Mekarski tramcars continued in use there until 1911, when they were replaced by electric trams.

The system was tried out in England on the Wantage tramway but did not find favour there because the compressor plant used more than four times as much coal as a steam locomotive.

http://en.wikipedia.org/wiki/Mekarski_system.

Now we learn something!

Rich

If we are going for green then why look to move it around at all.

A cleaner atmosphere, is that something for us on the earth to work for?

Absolutely. And that is a really good reason not to use compressed air powered cars. Because they create more pollution by requiring more energy than a gasoline vehicle to operate. Granted, the source of energy production is displaced to another location, and there may be some possibility that that energy is produced at a higher efficiency but the very large losses incurred in using it by this method negate any advantage.

Perhaps if you ran it on nuclear power plants, then maybe you aren't polluting the air but it is by no means pollution free. But hey maybe your state would like to volunteer as a site for a nuclear waste "storage" facility.

Ok, maybe you can power your air car only from hydro-electric plants. Great. Except that the clean energy that would normally be supplied by the hydro-electric plant is going to be made up for somewhere else in a fossil fuel burning plant.

I just don't see where it works out any way you look at it.

You are comparing 1 litre@330 bar with 1 litre of gasoline burned, I think that you forgot to include the 200 litres of air that is added to the litre of gasoline. Pistachios and oranges. The regulator is going to find itself filling with liquefied air, the pressure differential between +30 and -30 C is a 20% loss, the liquification of air is The air filling your cylinder after expansion is going to be liquified and about -100 (WAG) which means that your 320 litres has an effective value of roughly 100 litres, and at a cylinder temperature of -100. Ice buildup will be more than the weight of the tank. I would like to see the flexible hoses , connectors, valves, and piping needed. Also, the safe output of my electrical service is 200 A @ 250 v, or 500 KW. Shut the house down while you fill your tank.

As I recall, the Coleman refrigeration for nitrogen liquification works out about 100 bar @ 50º produces about 50% liquid @ -80. 330 bar to 10 bar should produce nearly 80% liquid. Just how much heat needs to be removed from the 320 l @ 330 bar to end up with 320/330/30°? The compressor output will melt solder and maybe even brazed joints. The expansion of the pipe will be unreal.

I know, we'll run a gasoline engine to heat the reduced temperature expanded gas to fun the engine. Maybe even using the compresed ar mixed with the 10 bar air. My goodness, we could develop 500 HP from a 1.3 litre engine running at 10 bar, except that the engine would end up weighing a ton (literally) to run that, so maybe we drop to 1 bar. Individual piston regulators so that you can throttle the 80/5 liquification from 330 to 1 bar. Liquid air/gasoline at 1 bar, 2 litres of liquified air to 1 litre of gasoline, but keep the engine down at about 6:1 compression to help prevent liquid lock. Make for a great dragster, but let me be sitting 20 meters back behind a 6 mm steel plate and a couple of air bags. That intake valve particularly should enjoy the -80 liquid stem side versus the 2000 inside burn.

A really stupid idea. And I think that nitrgen runs into it's critical temp and becomes superfluidic at around 330 bar. Try regulating that!

Riich

Thanks aurizon. I was just going to say that this is a ridiculous idea that should die and that anyone who has so little knowledge of how things work so as to think that it has any merit should probably switch over to one of the free energy sites.

But your comment takes the time to break it down in terms that are basically incontrovertible if the terms are understood or believed.

Wow! A great optimist RCapper! What do you when you have to change things around on one of your boards?

I only wish facts held sway in the face of denial. Sadly, I'm sure there will be argument.

I am not ( I hope) arguing for arguments sake, I really do think this has potential.

You are comparing 1 litre@330 bar with 1 litre of gasoline burned, I think that you forgot to include the 200 litres of air that is added to the litre of gasoline. Pistachios and oranges. The regulator is going to find itself filling with liquefied air, the pressure differential between +30 and -30 C is a 20% loss, the liquification of air is The air filling your cylinder after expansion is going to be liquified and about -100 (WAG) which means that your 320 litres has an effective value of roughly 100 litres, and at a cylinder temperature of -100. Ice buildup will be more than the weight of the tank. I would like to see the flexible hoses , connectors, valves, and piping needed. Also, the safe output of my electrical service is 200 A @ 250 v, or 500 KW. Shut the house down while you fill your tank.

In the meantime have a look at this link . So it is possible to run an engine on compressed air although I admit these models use CO2 which is slightly denser than air, but still food for thought!

I do not run around with diving bottles in my car, I certainly do not want air at that pressure in my car either, forgetting the weight and size for a moment of the bottle(s)....I would rather have LPG or similar, its far, far safer..... I have worked with 4000 PSI air on RN warships gun system Recuperators. Sealing was a problem and it is inherently dangerous, a real killer......like having 10 sticks of dynamite to work near.....only normal Oxygen bottles would I consider to be more dangerous than air at that pressure in that quantity......thanks but no thanks.....

A valid concern, but still an interesting idea don't you think, maybe there is some way around this, build several small tanks instead of one big one for instance.

DDJames:Where have you been? New to the Internet and the world of free energy scams?

Guy Negre and his Midi care have been around for years. Always promoting but to my knowledge has not SOLD the first one yet. He has sold licenses to manufacture the air car. Sold Midi Turnkey factories to manufacture the car. Sold the uninformed on the wonderful advantages of an air propelled vehicle but never mentions the drawbacks of the reasons for not having anything to do with air car investments.

"I am not ( I hope) arguing for arguments sake, I really do think this has potential." DDJames

Source Material For a Misunderstanding of Compressed Air

Take a good look at the Neal Air Tank and come back and tell us how it works.

e.g. If you do not understand the heat of compression of air or the energy in/of the ambient air you are not prepared to discuss the Midi Air Car!

I'm so glad that he believes that the worlds salvation lies in compressed air. It seems he has plenty of hot air available to him. Interheat, between stages? Boosts pressure/volume to the next stage, at the cost of back-pressure to the exhausting cylinder. Unexhausted air needs to be recompresed at a high energy cost. 28 years to build a library. Alexander would have loved him. What has a pneumatic drill motor (rotary) on a go-cart got to do with a car? Where is his cheap compression?

Solar Energy. I see no mention of how this solar energy is used or accumulated. No one denies that it would work, but the efficiency of 1. compressing air, and 2. using compressed air power are about the worst you could find.

And the air start would need a battery back-up for the creep in city traffic, where the start load would be higher than the regeneration available. And why would that add 12% efficiency for highway travel? Nothing to do with an air car.

Aside from selling some licenses, probably for 2 bits each. Makes his marketing sound better. In another 28 years, maybe he can have a a workable filling system. I'd bet he didn't fill his own scuba tanks, did he?

I know, you pump the liguified air back into the tank with a low volume very high pressure pump able to work over a mere 300° C range. For 2500 hours.

Ooh..Ohh.. I've got it. Put the air motor into the inflatable car. You won't care if you have a leak.

Add in the comparison of a 2 cc engine to a say 5 litre engine, and even your grandmother can see the wonder of it all.

Thank God he doesn't work for the government.

Rich

DDjames,

Sir, with every posting you display your complete lack of knowledge in physics and your total infatuation with the idea of getting something for nothing. Optimism is not magic nor appropriate as a perpetual state of being. Some things work and have value and some things don't. No amount of giddy faith in bad science or magic will make some things a good idea.

It is only your own ignorance of physical laws that prompts you to accuse those of us who have worked hard to gain some understanding of how things work as being closed minded. And you want to know what I do when I have to change a design? I experience this thing called learning. You should try it some time. It helps dispel ignorance. I don't get emotional about it because in the course of a week I make quite literally thousands of decisions and I am quite happy to keep my error rate below 1%. But it is only because I don't go off half cocked on assumptions. I spend the time to study what I am doing and pretty much everything I do works as planned. Minor tweaks do not count as failures.

But from what I've seen you don't do anything but champion bad ideas that could never work as billed. And that's all you do. You haven't built a "rotary impulse jet engine" except on paper and if you did you would quickly learn what a bad idea it is. I currently am managing about two dozen parallel designs all of which are or will function as intended. Alas, none will save the world or provide free lunch.

Very well put and not as unfriendly as a similar letter from myself could become.....!

Sometimes it just flows. Let me know if you catch me being too mean.

When we spar lower belts in class we only go hard enough that they have a chance to learn. There's no point in destroying anyone. With luck we may gain their respect. But hold no illusions, the opportunity for control of any other person is naught. Doof bist doof, kine pillen das helfen. (my spelling may be off)

Thanks Andy and have a good day.

You are most welcome.

Don't worry about the spelling in German too much anymore, its off slightly but fully understandable!

It is an art to condense what would take other people (er... me!) two pages to say into 3 0r 4 well-worded paragraphs, with perfect clarity. Even as an electrical engineer, I rememember enough of 1st year thermodynamics to see that this can only work with very fancy heat recovery systems to even consider energy efficiency.

50 kW not 500 kW.

DDJames: FYI there is another thread titled "Air Car." s/SS

I think if you design an air motor from the ground up to run at the wheel, you have enough mechanical flexibility with a compressed air system to bypass the rediculous albatross of an ICE coupled to a typical tranny. So eliminate the ICE, tranny, redesign your air motor - perhaps a sliding vane type with variable offsett and compression. This will at least get you to a point of decent technology advancement rather than throwing good technology at bad (i.e. reciprocating engines).

Lastly, windpower would be a fairly economical way to generate compressed air. Direct mechanical compression, no electrical conversion. Now,although this is being considered as an energy storage medium for some types of power generation - I can't believe that with all the heat typically lost in compressing a gas, that it can be very efficient.

Windmills, however, aren't completely about efficiency. If you have wind, use it.

Sorry mate;

pressurized air is about 10 times more expensive than electricity!

but it can change in the future!Who knows?

Now think of "everybody" driving around with a couple of scuba tanks in their car. Also, what about efficiencies. Balance the energy equations, so what makes this better than it being an electric car in the first place?

The power required to compress 1 cubic meter (35.3 cubic feet) of air per minute to a pressure of 90 PSI is 5.2 KW.

Don't worry, DDjames, this will not beat your pulsed rocket engine.

This subject came across other older blog on CR4. Someone who works in compressed air industry said all MDI setup is a nicely polished scam.

I would like to quote myself to the effect that: My support for the aircar is based on the premise that if you have a head of pressure of say 500 psi and it performs the same amount of work regardless of the source, (i.e., of whether that pressure is due to ignition and expansion of a fuel air mixture or if it is pre-compressed), then the aircar should work well.

As for Guy Negre being around with the aircar for so many years, what about Carol Shelby, generally acknowledged to be one of the greatest American car designers, he has been working on the OX-2 for even longer than Negre, that doesn't mean he's trying to scam anyone.

Also while it might be true that many people are content with the IC piston engine as it now stands, that doesn't mean that something better is not possible. Carol Shelby, the designer of the mustang, probably knows as much as, or more than most people about the IC piston engine and its capabilities, if he is not satisfied (and he is not), then I think there is room for improvement and anyone who has a good idea should come forward. At least my RPJ design has the advantage of possessing a means for getting compressed air and fuel to the combustion chamber in a fully sealed environment and then igniting it. This is a huge step forward in any rotary design, whether the final power delivered will be anything like that of an IC piston engine will have to be seen. The aircar also has potential, no-one has had the audacity to experiment with air at such high pressures.

"My support for the aircar is based on the premise that if you have a head of pressure of say 500 psi and it performs the same amount of work regardless of the source,"

I you understood only a little bit about thermodynamics you would realize that this statement ignores so many of the reasons why the air powered car is a bad idea that it isn't funny. You can not isolate and look at only one tiny part of a system and claim that it makes the whole system a good idea. You have in another blog attempted to justify the validity of your pulse rocket engine based on the completely inapplicable fact that a catastrophic failure of an air cylinder makes a big explosion. Your statements are devoid of logical reasoning. There simply is not logical connection between what you say and what you claim it infers. You would do well to get a good physics book and read it. Your insistence on the illogical connections you try to make in order to justify your simply wrong assumptions is beyond comprehension.

You cannot simply state a fact and then say because A is true B must also be true based only on the fact that you believe it is. If that's all it took to make things work then I should be able to levitate and do subatomic tunneling through solid objects. I've always felt like I should be able to do those things. So far reality keeps getting in the way.

I you understood only a little bit about thermodynamics you would realize that this statement ignores so many of the reasons why the air powered car is a bad idea that it isn't funny. You can not isolate and look at only one tiny part of a system and claim that it makes the whole system a good idea. You have in another blog attempted to justify the validity of your pulse rocket engine based on the completely inapplicable fact that a catastrophic failure of an air cylinder makes a big explosion. Your statements are devoid of logical reasoning. There simply is not logical connection between what you say and what you claim it infers. You would do well to get a good physics book and read it. Your insistence on the illogical connections you try to make in order to justify your simply wrong assumptions is beyond comprehension.

All that I said in that blog was that reaction forces seem to be comparable to, or even exceed expansion forces. And I had given a reasonable example proving this, namely that given an identical load and an identical amount of fuel, a rocket lifts the load for a greater difference than the super-gun, which is heavier and bigger by a factor of ten! You don't seem to be addressing the fact that this is something that is deserving of being looked into.

Your assertions are absurd and illogical and you are unable to see the disconnect between some minor truth and what you for no logical reason insist that it "proves".

Go to school or get a book and learn how to construct an argument that holds water.

Here is a good site for you to study:

http://www.lhup.edu/%7EDSIMANEK/museum/unwork.htm

The discharge from your air motor is going to be about -100 or more, versus inlet of 30. ICE has a peak temp/presure of around 20,000 psi/2000° c. The exhausted gases will be about 700°. The EXPANSION of the gas is what drives the engine. A 500 cc cylinder takes only 400 cc of air STP per cycle. Your air engine is going to need at your figure of 500 psi discharge, not accounting for the temperature drop, 3 liters of air SP. The T drop will probably boost the air quantity to 6 to 10 liters, per single cycle, Notice that one means of filling the tank with liquid CO₂ is to rapidly refill the tank after fill/use cycle. That's the temperature of the air going into your cylinder. Those snowflakes you see with a CO₂ fire extinguisher are flakes of frozen CO₂. at a temperature of around -80 C or -112 F.

Oh, and I'd forgotten. The temp of liquefied air is +77° K, -175 C. -340 F. That's based on expansion to 1 bar from 100 to 350 bar. Regardless of any staging. And the heat of compression is demonstrated by the autoignition of diesel fuel at the top of the diesel compression stroke, at only 20:1 compression ratio. And you want to compress to 330 bar.

Open your scuba cylinder and watch the liquid spray around. Try a CO₂ extinguisher.

Go to a scuba shop and watch how much heat is generated at 100 bar.

People are trying to help you understand that. And maybe have some fun with each other on the way. Not at your expense.

Hi DDjames.

I think your concept has much more potential than the air car.

It's not about audacity. Such a high pressure has a price: special seals, pressure vessels (highly regulated) and a huge amount of energy to produce it (+filter + dehumidify). I'm not saying such a car is not moving. But all Guy Negre's advertising is focused on how that car works and almost ignores or minimizes the price of high pressurized air. The air car is nice but its efficiency is much under any reasonable horizon...

Perhaps I should explain just what exactly led to the sudden change of heart I had experienced with respect to the MDI air-car, at one time I was as firmly opposed to it as anyone and denounced it as a complete scam. But as I kept looking at the figures it began to emerge that maybe I was wrong. For instance the web-site says that a single 320 litre capacity tank charged to 4000 psi ( about 300 bars) would last for 7hrs – 8 hrs at speeds upto and exceeding 60 kmph. At first sight this seems ridiculous and I even did some calculations to prove that these figures were completely false. Then I realised that at 4000 psi the combustion chamber need only have a volume of 8 cu cms. this would expand 120 times to a volume of 1000 cc aprox. to bring the original 4000psi down to atmospheric pressure (32 psi ). You can't straight away use 4000 psi without damaging something, so the air would first have to be expanded in a secondary combustion chamber to 500 psi before being fed into the cylinder. Suppose the engine is running at 4000 rpm, then in one minute 8 x 66 = 528 cu ins so the tank of compressed air in the car would last for 320000/528 = 606 mins = 10hrs 6 mins. But if you are using a pressure of 500psi to drive the cylinder then even when the tank which was originally filled at 4000 psi , it will still have enough air at enough pressure when it is one sixteenth full to drive the piston, so say a running time of 7hrs – 8 hrs, at a performance similar to that to equal to that of a 1 litre piston engine seems about right and not unreasonable.

Again, take the question of the time it takes to charge the tank. We know that it would take a 500KW compressor approx 2 mins to fill the 320 litre tank to 4000 psi. This means that it would take a 250 KW compressor 4 mins to fill the tank and so on. If this is continued you find that a 4KW compressor takes approx 4 hrs to fill the tank, which is exactly the time quoted by the web-site. In short there were too many coincidences beyween the figures I had calculated and the at first highly unlikely figures featured at the web-site. When I read later on that a tiny 2cc tank was able to power a compressed gas CO2 engine used for model air planes for five minutes. My doubts only increased. Further the very fact that TATA Motors, one of the biggest car manufacturers in India has decided to go in for a tie-up with MDI and that it has widely publicized that fact gave me even more food for thought. They are no fools after all. So I suppose only time will tell, if nothing happens within the next year or so then take it for granted that it is a scam.

Instead of wasting energy from 4000 to 500 psi they use a 3-4 stage 'uncompressor' that take the air down to ambient in 3-4 8:1 expansion pistons of greater size and lower pressure. the fits one, from 4000/8 = 500 psi, second 500/8 = 63 psi, third 63/8 = 8 psi, all above gage pressure of 14.6 psi of course They would get larger in proportion and have interwarmers, but it would work.

In mines or other places they can be made to work, but they can never be efficient.

That's the rub, efficiency, as well as endurance. I would have to calculate the power that 1 cc of 4000 psi air will produce in going through this engine.

http://www.steamcar.co.uk/

http://www.stanleysteamers.com/

http://www.firedragon.com/~kap/Barrett/

http://www.lightsteampower.freeserve.co.uk/

This one just keeps coming back and getting mentioned..........(from one of my previous posts after I assessed the site and the technology behind it)...........

I was going to post a blog on this yesterday but was sure the article would turn up on this car, and here it is. Well it all looks well and good, but isn't the energy density of air 17Wh/L as opposed to, say, gasoline at 9000Wh/L. As far as I was aware compressed air could not be produced and harnessed effectively to make it any sort of viable fuel.

Sure the cars themselves don't produce pollution when running (actually the press releases states that they produce negative pollution as the car also uses air from the atmosphere, which it filters before hand). It all seems like yet another smoke and mirrors development to move the pollution sources away from the city (power plant producing the energy to power the compressor to produce the compressed air that powers the cars engine), while at the same time producing even more pollution (high value energy source being converted into lower value energy source), or what I like to call "the clean energy scam". I am further baffled by their comments regarding using the engine as a power generator (taking a high value energy sources such as gas and petrol and producing a much lower value compressed air energy source), and having the option of a dual engine system to use a petrol engine to power the main engine AND a compressor to refill the air tanks while driving .

This would perhaps be a promising transport development IF we could generate the power (to compress the air) from a clean renewable source rather than coal, oil, solar etc (geothermal perhaps).

Additional articles on the car......

http://gizmag.com/go/7000/

http://www.theaircar.com

If only it were true, but it just isn't. What it boils down to is another smoke and mirrors scam (and quite a blatant one). Have a CAREFUL look at the air car website and the information in it (especially the "how it works section"). You don't have to be an engineer to see why this design does not and will never work (and that is ignoring anything regarding compressed air storage and safety).

If only it were true, but it just isn't. What it boils down to is another smoke and mirrors scam (and quite a blatant one). Have a CAREFUL look at the air car website and the information in it (especially the "how it works section"). You don't have to be an engineer to see why this design does not and will never work (and that is ignoring anything regarding compressed air storage and safety).

But if it doesn't work and will never work, how do you explain the fact that model airplanes running on compressed CO2 do work, and work quite well. So much so that in many instances they are the preferred engine for model air-planes. (The co2 is compressed to roughly 4000 psi in the fuel tank. ) follow link

Toys don't have to be efficient, they are for entertainment. You have no understanding whatsoever of thermodynamics and so as a result everything you say is pretty much just wrong. No one said it couldn't be made to function. When he says it doesn't work he just means it works so poorly and is so inefficient that it doesn't "work" in a practical sense of something that anyone would waste their time doing. I may make a cool toy because you don't care about the cost of operation but anyone unfortunate enough to have such a car would quickly come to rue the day they bought it. Your faith is based on completely ignoring the real issues.

You really should look at this because it describes your behavior to a "T":

http://www.lhup.edu/%7EDSIMANEK/museum/psych.htm

I am going to have to agree with RCapper on this one (although without all the rudeness). With regard to model airplanes CO2 can be used (no one is disputing that), so can a rubber band engine. Both are possible forms of power and both are used but neither are common.

Quoting the breaking of laws and the finer points of technical detail is all well and good and it provided proof of just some of the many reasons this design has never worked the way it is being marketed (hence the scam), but I think people can get a bit carried away trying to get a bit too technical when the person putting forward the questions may not understand. Now I am a power engineer and part of my job is to evaluate technologies and developments, especially in the areas of power generation, storage and transmission. The air car is not what it says it is.

From post #50 -

Quote by Rcapper in 1910. "There can't be any such things as air-planes or I would be already using them!"

Please bear in mind that although this statement can be true if a person ignores facts or does not understand the physics behind something (such as early comments by a famous lecturer who said that a rocket engine cannot possibly work in a vacuum), the case of compressed air power generation is well understood and scientifically proven. Compressed air and steam-powered vehicles have been around for as long as electric and gasoline powered vehicles. The physics, advantages and limitations of each are well understood.

Considering how long this thread has been going on I don't think any of us are going to be able to sway your opinion, as you just seem to be trying to come up with new ways to justify your opinion, rather than listening to what people (who probably know far more about the subjects and underlying physics behind it than you) are trying to explain to you. Questioning things is a great way to learn, but I don't think you understand the underlying physics behind what you are questioning. I think the next stage is for you to take what we have all said and have a look at the science behind the technology, rather than going off of what some websites have to say about the subjects (now-days it can be very difficult to tell the scam websites from the real ones).

From post #13

I am not ( I hope) arguing for arguments sake, I really do think this has potential.

I had hopes too when I first assessed the technology, but they were dashed when I closely read the website and discovered it was nothing but a scam. Still, for every 1000 un-workable piles of backyard invention or scam garbage there will be one potential-ground breaking discovery made or new idea proposed. I continue to look, keeping an open mind.

Are you seriously repeating DDjames's fabrication of me saying something 45 years before I was born as though I actually said that? He made up that whole dialog. Please don't mis-quote me!

And I resent your referring to me as rude. Terse and brutally honest. Frustrated, but have you followed the entire discorse?

I think it is quite inappropriate for this guy to have made up an entire dialog that never happened.

Well I thought it was plainly obvious that the quote was nothing more than the use of the old Wright brothers flight menality addage, used by DDJames to indicate that something people thought couldn't be done before was obviously done, and if this argument was about flight back then you would be making comments like the one indicated (obviously you did not make the quote back in 1910). This sort of misquoting has been used for a long time and is one of the cornerstone arguments of the free-energy followers. The purpose of the reuse of that statement was to try and explain that this sort of thinking does not work because you are not comparing apples with apples (so to speak). Another common one is "Well everyone thought you couldn't fly or go to the moon but they did, so that is why free energy generation is possible." <sigh> I don't take it seriously and I doubt anyone else did either.

And, well, you were getting fairly short with the guy (its not like he invented another free energy generator and was trying to push it on the world). It certainly doesn't help when trying to explain to someone who doesn't appear to want to listen. Clear heads and all (and I have followed most of the thread). Besides, I would like others to point out to me if I was getting to short with a poster.

I appreciate your response.

Sorry to misinterpret your use of his fabrication. Perhaps I shouldn't make responses right after I wake from sleep.

If you trace the thread back far enough, and my interaction with this fellow actually spans numerous threads, you may see that I have gradually become more blunt as it progressed, though clearly to no good end. If there are particular instances where you feel I crossed the line, so to speak, I would like to know since I do make an effort to not be rude, though sometimes after repeated efforts to be tactful it seems that the only thing left is to be quite blunt.

Frankly I don't expect for him to ever move from his position but as long as people respond to me I tend to make a response. The reference to the things that don't work site is not to infer that he thinks he has perpetual motion just to point out that he uses the same forms of non-reality based reasoning as those people do.

But his infatuation with the notion that high pressure gas is the answer to increased efficiency seems totally unshakeable. Good luck with your efforts to help him see it differently.

If you have a close look (close) at the information on MDI's website it becomes painfully clear. I dread to think that a bunch of mechanical and electrical engineers could be that stupid <cringe>, hence it's a scam (rather than lousy engineering knowledge). You may have missed the obvious blunders (mainly because they are so obvious). A case of not being able to see the wood for the trees.

Yes I have seen your rotary pulse jet idea. I believe it has been covered by others more qualified and knowledgeable than me in that area. All I am going to say is that I don't believe you are actually comparing apples with apples (especially with regard to your expected efficiencies, zero pollution, available torque, etc). I may be wrong (my experience is mostly electrical) but I think you will be rather unpleasantly surprised when the engine force cannot overcome the load created by the onboard air compressor. I don't remember seeing it anywhere, but are you capable of performing a system analysis using a simulated model of your proposed engine (or perhaps a small scale model).

The MDI air car scam has long been regarded as an idiotic idea by most people who have worked with compressed air (or who stayed awake in high school physics class). In the best of all fantasy worlds, compressed air would work as a spring: You squeeze the spring, and it gives you back virtually everything you put in. (Even in that fantasy case, you'd only be storing energy you paid for.) But compressing air is not even remotely close to that efficient. Here's a quote from a US DOE pamphlet:

Compressed air is one of the most expensive sources of energy in a plant. The over-all efficiency of a typical compressed air system can be as low as 10%-15%. For example, to operate a 1-horsepower (hp) air motor at 100 pounds per square inchgauge (psig), approximately 7-8 hp of electrical power is supplied to the air com-pressor.

Consider the fact that electricity is produced at about 38% efficiency in the US. If you compress air with your home compressor to fill your "air" car's tank, the well to wheels efficiency would be about 3-5%, which makes the average ICE car look like a marvel of efficiency by comparison.

This is anything but rocket science. Just feel the head of a running air compressor. All that heat loss is a sign of inefficiency.

(This is in reply to Rcapper's post.)

You have in another blog attempted to justify the validity of your pulse rocket engine based on the completely inapplicable fact that a catastrophic failure of an air cylinder makes a big explosion.

Rcapper, the only way to illustrate the fact that your belief that technology is preordained is to describe one of your arguments. I ask the questions you give the answers.

Question: Do you believe that highly compressed air as found in a charged scuba tank is capable of catastrophic failure if accidentally ruptured. We have had several examples in this thread illustrating this. One example, describes how a scuba tank whose valve had sheared went through two concrete blocks. Do you believe this is true?

Rcapper: Yes.

Question: Let us get this straight, so a highly compressed air tank would be very dangerous if ruptured because of the extreme levels of energy it contains ?

Rcapper: I guess so.

Question: What if the pressure was reduced to safe levels and the tank equipped with a valve to CND Nozzle, would it be possible to channel these potentially destructive forces into a constructive force that could be harnessed and used.

Rcapper: No!

Question: Could you elaborate on that answer, why would it not be possible, to channel that energy in the manner I have suggested?

Rcapper: Your arguments are illogical and have no meaning. If such a thing could have been done, I would be using it now, instead of my IC piston engine.

Your statements are devoid of logical reasoning. There simply is not logical connection between what you say and what you claim it infers. You would do well to get a good physics book and read it. Your insistence on the illogical connections you try to make in order to justify your simply wrong assumptions is beyond comprehension.

Quote by Rcapper in 1910. "There can't be any such things as air-planes or I would be already using them!"

So finding yourself unable to put together a competent technical reply you now resort to writing fictional dialogs. You make a fool of yourself every time you post. You would do yourself and everyone here a favor by going away. You have no support for your outlandish conjectures and you just don't see it.

So finding yourself unable to put together a competent technical reply you now resort to writing fictional dialogs. You make a fool of yourself every time you post. You would do yourself and everyone here a favor by going away. You have no support for your outlandish conjectures and you just don't see it.

So what is there to see, just make a rough calculation. You have a 8 cu in chamber filled with compressed air to 4000 psi (I am referring to the RPJ here) presumably if it is ruptured it will definitely go through two or three concrete blocks right? OK , lower the pressure in the chamber to 500 psi, fit a CDN (Convergent divergent nozzle) to it, equip the nozzle with a valve and when the valve is opened what happens? Nothing right? At least according to your calculations, nothing happens, the three concrete blocks cease to exist, the pressure that caused the chamber to go through those three blocks no longer exists at 500 psi? Who is talking about fiction now? There will definitely be pressure. The presence of the CDN means that the force will be a directed force, it is possible to extract useful energy from this, and to do so more efficiently probably than an expansion force ( read piston and crankshaft) can possibly achieve.

You insist on failing to understand that there is a real issue of matching the load to the source of power. Did you look at the reference I sited on the comparison of different engines? Jet engines are not more efficient than reciprocating IC engines!!! It is clearly stated. They have a higher power to weight ration which is great if you want something to fly.

And yes you do have to do calculations to clearly understand how it "seems" has no bearing on the reality of the situation. That is the point of the web site on inventions that don't work only some of which were perpetual motion machines.[p[ You are using the same uneducated ignorant justifications that all those people use. Just because you aren't touting perpetual motion doesn't mean that applying the same wrong thinking makes you right. You are simply wrong in your assumptions and clearly no amount of fact or highly trained engineers telling you so will sway your faith in your religious fervor for your pet idea. It is wrong. I have referred you to the data and you insist that your "feeling" about it makes it right. Please, build your piece of crapp machine, waste your money and discover the truth! Oh and quit wasting our time, your arguments are childish and without substance and you clearly have no intention of changing your position because of anything silly like the facts or the truth.

You insist on failing to understand that there is a real issue of matching the load to the source of power. Did you look at the reference I sited on the comparison of different engines? Jet engines are not more efficient than reciprocating IC engines!!! It is clearly stated. They have a higher power to weight ration which is great if you want something to fly.

Has it occurred to you that the Rotary Pulse Jet design does not fall into either category. Let me explain, the RPJ develops a pressure of about 500 psi in the combustion chamber through ignition and combustion of gases, a pressure 500 psi (35 kg/cm2) is normally only reached in medium to fairly large size rockets. So the efficiency is much greater, it is more like a pulse detonation engine, than a rocket or a jet. In a normal engine of those types there is no real detonation only conflagration, which is a kind of slow, fuel intensive, (comparatively) low pressure burning. To state one instance the original pulse jet (buzz bomb) had a compression ratio of only 2:1, while in a pulse detonation engine, the fuel air mixture is actually detonated (exploded) giving much higher pressures in the combustion chamber before release.

"Has it occurred to you that the Rotary Pulse Jet design does not fall into either category."

This statement is incorrect. It does fit because of the speed at which the gases exit the combustion chamber is too high to transmit power efficiently to the mechanism.

And this: "a pressure 500 psi (35 kg/cm2) is normally only reached in medium to fairly large size rockets."

Does not logically prove: "So the efficiency is much greater"

You just can't say one thing and then claim it means something without substantiating the connection. That is essentially a form of expo-facto logic. The black cat crossed my path and that caused me to an accident.

And rockets are not efficient. Turbojets are not efficient. Turboprops and turbofans are more efficient than a rocket or a turbojet but still for the same amount of energy expenditure you will get much more useful work from a diesel IC engine. If you could get to space with wheels it would be powered by a diesel IC engine. But there just isn't any other way, thus far, to get there from here.

Check this site: http://people.bath.ac.uk/ccsshb/12cyl/

This diesel IC engine exceeds 50% thermal efficiency. Can you prove with anything other than "it seems that way" to you that your engine or the air car can even approach this level of efficiency? You can not because it doesn't and I'm sure you don't have the calculations to show because if you did and they were correct you wouldn't be arguing because you would know the truth.

You simply cannot, on an engineering site defend your position with only your belief. And thus far that is all you have offered. Your logic is not substantive because it references are faulty or only lead back to your belief or nonsensical connections to actual facts that you believe are linked, but they are not.

Just answer a few questions please:

Did you go to the Wikipedia reference I gave you comparing engine efficiency?

If you did, did you understand the table that showed relative efficiencies of different engines?

Do you understand and agree with the reasons stated as to why no one uses a turbojet on any modern airplane?

The car with no wheels is a bed for the night <cough>.

Ken I would have to say, that even though it was an excellent reference, I am not fully convinced: "A typical manufacturing facility has a 200 hp compressor requires 215 hp to operate. " Well what's wrong with that, so the government is carping that it costs more to compress the air than the energy equivalent of that compressed air, but it still works out cheaper than gasoline on the road right?

...but it still works out cheaper than gasoline on the road right?

No. Gasoline is produced with 82% efficiency, from well to pump. From tank to transmission (through an ICE) the efficiency is about 20% (higher with a hybrid). So overall efficiency is about 16% (ignoring transmission losses and rolling friction, and other losses that both air cars and ICE cars share).

The comparable figure for well-to-plug-to-compressor-to-air-motor-output is (let's say, to keep the math simple) 4 percent (ignoring transmission losses and rolling friction, and other losses that both air cars and ICE cars share). Thus you've used energy about 1/4 as efficiently by using air power.

Industry has been using both air and electric motors for many decades. Air is never routinely used for simply making things move: it is far too inefficient. It is used when there is a compelling advantage for its use for reasons other than energy efficiency: linear motion with an air cylinder is cheap and easy; it's more expensive with electric linear motors. Electric motors are potentially problematic in explosive environments, so you can pay for expensive explosion proof equipment or use air instead, etc.

Read up on Joule's work-heat equivalency experiment. Compressing air must generate heat per Boyle's laws. In practice, that heat is lost. That means energy is lost.

If you like the MDI idea, you'll love the Searl Effect Generator.

Seriously though Rcapper, I did visit the web-site you quoted, I am not advocating a perpetual motion machine by any means. Everyone knows that the golden law of physics is ' nothing for nothing.'

Hottech

The power required to compress 1 cubic meter (35.3 cubic feet) of air per minute to a pressure of 90 PSI is 5.2 KW. Don't worry, DDjames, this will not beat your pulsed rocket engine.

Thanks for your support. I have been meaning to reply to your post, for some time, right now seems to be a good a time as any. You are probably right, the Rotary Pulse Jet does seem to be a better option than the Air car. One thing that has emerged from this discussion that seems to be certain is that cooling of the rotor and the exhaust system shouldn't be a problem! Although the exhaust itself will have to be treated by mixing it with ambient air and then passing it through a water cooled radiator. I am already working on some models, but to make the actual thing will require a little more time and capital. Cheers! D James

I am not sure I follow you in the details on your engine. But as long as you work on your model using exclusively your time and money, nobody will blame you, regardless you're right or wrong in your predictions. My only suggestion is don't bankrupt your family for this!

I am willing to answer any questions you might have about my engine design. Just send me an e-mail.

I am already working on some models, but to make the actual thing will require a little more time and capital.

Perhaps if you rewrote your materials with the help of a physics prof, and someone who can do the math without so many mistakes, then you could get funding together.

Frankly, your materials seem intentionally fraudulent. Why "some models"??? build just one combustion chamber that works. Who would make a combustion chamber out of nylon??? Aluminum is cheaper, iron is cheaper, steel is cheaper. I can build a combustion chamber in my shop for essentially nothing but my time and a little metal scrap. It seems the only reason for building it in nylon would be to say: "Oh well, of course I can't build a working prototype without more money -- I need investors."

Build one real combustion chamber, fire it, and measure the thrust and the duration of impulse. You can do this for next to nothing, even in the scale of someone collecting unemployment. If you believe your idea will work, and back that belief up with real math, then get the money to do just this very small thing: there are shops who would build it for you for free if you can present it plausibly. If you get whatever ludicrous thrust you claimed, then you can get more money easily. You can have a test finished in one week. Go for it. Let us know, next week, how it goes.

If you want to speed this process up, calculate the energy of your combustion chamber with 125 psi air, and the stoichiometric amount of fuel that goes with that (a drop or two?). Find a hobby rocket with the same energy: the combustion chamber and nozzle are pre-built for you. Fire that and measure your thrust. You could have your answer tomorrow.

Thanks Ken. There is a lot of truth in what you have to say. Maybe I will take that route. I just have to save up a bit! The reason I built the nylon model was not to use it per se, but to have something to give to a fabricator and say, look this is what I want, build it to exactly to these specifications, rather than trust to blue-prints etc., As for the maths, I did make the changes that you had suggested and the site does look better as a result. Of course there is a lot more that could be done……

Guys... its really simple. there is just not enough energy in compressed air to make this EVER viable. go back and do your homework with lancaster's energy fundamentals: http://www.tinaja.com/glib/energfun.pdf

These guys ARE a scam. just as big a scam as the brown gas/hydrogen power guys. Or the super capacitor storage guys. or the.. on and on and on.

People want alternatives so badly that scammers like these guys are taking advantage of them every day. these guys are stealing big money from licensees around the world.

heck even the discovery channel show talked about these guys having some way to make compresses air "using compressed air"... and even went on to call it perpetual motion. now thats a great way to add credibility to your cause! claim it's a free energy source!

Thanks for an interesting post. The link was excellent especially considering the detail, which is available. For instance there is a lot of information on the use of hydrogen as a fuel that is not usually available, including its corrosive effect on metals. After reading this the fuel cell just does not have the appeal it used to, apart from the other problems there is also the possibility of highly toxic emissions.

The article certainly puts the use of compressed air in a poor light giving a comparison of 17 Watthour/litre as opposed to 9000 Watthour/litre for petrol. Making it one of the lowest energy content alternative fuel sources.

There are also several possibilities quoted at the end of the article that can be explored, including direct broad band solar rectifiers and metalloradicals.

In the meantime the Rotary Pulse Jet Engine (http://www.geocities.com/rotarypulsejet - sorry, link no longer available) seems to be a distinct front runner, since it does use petrol and does so, at least theoretically, more efficiently than an IC piston engine!

"and does so, at least theoretically, more efficiently than an IC piston engine!"

Theoretically based only on your intuition. No thermodynamic analysis, no working prototype. And for your one opinion that this is so I have witnessed several highly technically trained opinions to the contrary. Where is your experimental data to back up such outlandish statements? Note that although you now seem to be convinced that air powered cars are a bad idea, you originally thought they were a good idea for the same reason you still apply to your rotary pulse jet engine.

In the meantime the Rotary Pulse Jet Engine seems to be a distinct front runner, since it does use petrol and does so, at least theoretically, more efficiently than an IC piston engine!

You can hardly imagine how arrogant and ludicrous this sounds.

Here is a key paragraph from your website:

Assuming that the combustion chamber is in the form of a cylinder with a diameter of 2.5" the pressure on the back plate can easily be calculated by multiplying the area of the back plate by the internal pressure within the combustion chamber. This yields 1.25² x 3.14 x 500 = 2453.12 lbsf on the back plate, this force is multiplied by two since both combustion chambers are firing simultaneously and contributing their force in the same direction. Thus the total force on the back plates = 2 x 2453.12 = 4906.25 lbsf. When the valve to the CDN opens this pressure is converted into kinetic energy.

Per your "logic," The "pressure" (you mean force) on the "back plate" of my shop air compressor tank is 125 psi * pi * 7^2 = 19232 lb. Would I not have to be to be idiotically gullible to believe that putting a nozzle on the end of this tank would give me 19232 lb of thrust??? Several times, I've connected a hand-held nozzle to this tank (not too far in size from your de laval nozzle) and have experienced thrust of... drum roll as sweat pours from my brow... almost an ounce. You could double or triple your calculated thrust by simply reshaping your combustion chamber to have double the "back plate" area. Following your logic, just make your combustion chamber conical, with a "back plate" of 4" dia, and with the small end of the cone at the nozzle end. 6280 lb of thrust, per your logic! Can you imagine how profoundly idiotic this seems?

When the valve to the CDN opens this pressure is converted into kinetic energy.

Pressure does not "convert" to kinetic energy.

You go on to say: Thus if the rocket pods combustion chambers work at 70% efficiency i.e 0.7 x 4906 = 3434 ft lbs all of which is available as torque, compare this with the 160 foot pounds of torque generated by the Chevy v-8 on the last page!

Even setting aside the ludicrous notion that your little rockets produce anything even remotely close to 4906 lb combined thrust, this thrust is per your own drawing and description only available for a tiny portion of the rotation.

By now you should have had loads of time to produce a simple combustion chamber, filled it and done a test firing. You seem unable to bring yourself to actually doing that. As I said previously, you could build a chamber in iron, steel or aluminum for a couple dollars. Failing that, you could use the rocket thrust calculator I provided a link to earlier -- if I recall, your pressure figure (500 psi) and a more plausible temp of 2000F (instead of 2000C) would produce a thrust of a few pounds through an optimally shaped nozzle.

I really think you need to crack open a physics text -- unless you really want to come across as a fraud.

Ken-

Thanks for taking the time to point out the details of why this is such a ridiculous idea.

I lack the patience or the time. The shear magnitude of discrepancy that your post illuminates has me laughing al the way to lunch.

Keep up the good work!

Arrrgh -- I just lost my response to your post.

Basically, it said thanks.

In finding vendors for hybrid vehicle pieces, it seems like half the time, I am chasing vaporware: prototypes, or even ideas promoted as if they are production items; ESU units from EEstor with wild claims, but lots of investment; Real batteries with $30,000 price tags for what should be a $10,000 vehicle... sometimes I feel like I need a private investigator working full time to sort through the scams, the half truths, the truth...

Knowing the consternation scams, near scams, and over-hyping "real" products can cause, I am loathe to see ludicrous ideas promoted as viable contenders for increasing efficiency. But debunking this stuff takes too much time, and I appreciate your efforts too. We may not be able to clear the world of frauds, but it would be nice to have at least a zone of rational thinking on CR4.