Bob O'Neil Air Engine

[Joe1]

In my opinion, I am not in a big hurry to construct a Bob Neal look-alike machine.  There were several air power builders during his time period, but concrete information is sparce.  So, I see Bob's patent drawings as a view into this secretive subject from that era.  I believe that all the air car builders were utilizing the save physics process, and since pv=nRT, the air liquifiers are also using a similar process, (at the basic physics level), to achieve overunity effects.  Overunity meaning to extract useful energy from the ambient energy of the atmosphere.

Possibly we could discuss overunity, and begin from the most basic level.  Take heat for example. 
1.  Heat can travel due to thermal radiation, which is an infrared wave, in physics it is called "black body radiation".  This is how those motion sensor lights you can buy for $9.99 work.  This is a fast process, but I think the amount of energy transferred will be quite low, unless you have access to the sun. 
2.  Heat can also travel by conduction/convection which would be the molecules of a solid or of a gas bumping into each other and sharing their respective energy content.  With a gas, this convection will cause the heat energy to flow through the gas at a defined rate determined by the amount of gas molecule collisions.  Heat applied to a pipe with gas inside would also be this process.  This process is able to move large amounts of heat energy, but is still a relatively slow process. 
3.  Finally, we have the molecular heat energy, (maybe someone can find a better term for this?).  This is the internal heat of the gas which can be changed by expansion, expansion against a load, and by compression.  This method of heat transfer can move large amounts of energy, AND it can occur very fast.  I think that #3 is where the overunity, or ambient energy extraction will occur.

Could someone out there comment on these three items?  Is this list complete, is it accurate?

Now look at pressure.  With a gas, there is a unique process where it is possible to create adiabatic compression and expansion by using a pressure wave.  For practical purposes, a pressure wave can be considered non-dissipative, (much more so than other methods).  This is an available tool to use with gas manipulations.  A pressure wave can co-exist, or be superimposed upon, a steady flow of gas, with little or no interaction between the two effects.

As mentioned earlier, the vortex is another physics process that is available.  This is similar to a pressure wave, but is turned back on itself.

In order to extract energy from the atmosphere, our machine needs a connection to that atmosphere.  The machine walls will conduct heat as in #2 above, but that is a slow process.  For the fast molecular heat energy transfer we need to access the atmosphere gas molecules directly.  Trippler style air liquifiers access the atmosphere at their machine outlet, where is located the expansion nozzle.  Bob Neal has two locations with access to the atmosphere molecules, his inlet valves, and his engine cylinder outlets.

Bob Neal has several checkvalves throughout his machine.  Are checkvalves used for heat transfer?  I say no.  Checkvalves are used with pressure differences.  If we create a pressure difference at Neal's inlet valves, and then open those valves, then the atmosphere will rush in.  The greater is the pressure difference, then the faster will the atmosphere gas molecules rush in.  If we look at Neal's machine inlet from the pressure point of view, then the question becomes:  What is the most energy efficient method to develop a pressure differential at the machine inlet?

Are there other basic physics processes that are not listed here?  Discussing heat or pressure is just choosing a convenient point of view, since in the end, p,v and T are all intertwined together, and all will need to be accounted for.

Comments or further discussion would be appreciated.

[Tom Booth]

The main things that strike me as important to keep in mind are 1. Neal's patent claims that the so-called "compressor" doesn't actually compress any air but works at atmospheric pressure. Low pressure air at about 15 psi (1 atmosphere) is pumped to the tank. The tank pressure is much higher, if I remember right about 100 psi.

The second thing that strikes me as important is the passing reference about the heaters used to bring the air (from the tank) up to or just above freezing just before, or as it enters the power cylinders.

I have to assume the tank is sitting in normal ambient. Probably somewhere between 50 to 80 F.

So you have warm ambient air going into the compressor ending up as very cold air in the tank needing to be heated back up for power production.

The implication being that somehow the process of "compression" is cooling the air down to well below freezing. Water cooling alone could not do this. The only possible mechanism I see for accomplishing such extreme cooling is the big valve at top of the cylinder. The incoming ambient air being "throttled" resulting in Joule-Thompson effect cooling.

This type of cooling is used industrially in liquifying gases, refrigeration, air conditioning etc.

"The throttling process is of the highest technical importance. It is at the heart of thermal machines such as refrigerators, air conditioners, heat pumps, and liquefiers." - from M.J. Moran and H.N. Shapiro "Fundamentals of Engineering Thermodynamics" 5th Edition (2006) John Wiley & Sons, Inc.

http://en.wikipedia.org/wiki/Joule–Thomson_effect

If that is the mechanism used in the Neal engine, to me this also provides an explanation for how the "equalizer" works, as a kind of thermal pneumatic PUMP.

If the air were "throttled" so as to reach an extremely cold temperature and delivered to the equalizer - still very cold, if not actually liquified, then by comparison the equalizer would be EXTREMELY HOT at ambient temperature. I don't see that the heat transfer under such circumstances, by conduction, would be "too slow" to produce a rapid thermal pumping effect to drive the air into the tank. Almost any pump of any kind you might care to look at other than a rotary or screw type pump consists primarily of two check valves. If the equalizer is a thermal pump activated by temperature change then it needs no other mechanism.

The cold air or liquid air having entered the equalizer warms up and expands so its pressure rises rapidly from 15psi to above 100psi and it is forced into the tank. As it rushes out into the tank it leaves a vacuum which draws more cold air into the equalizer.

To me this fully explains the working mechanism behind the engine 100%.

If it is wrong, I can't really for the life of me see any other possible solution.

I think this could be tested by constructing just one such "compressor" cylinder with such a "throttling valve" and attach the outlet to a tank (with an equalizer) and see what happens.

The one cylinder would not have to be a full working engine. The piston could just be driven by a motor on a bench. The valve could be made adjustable. Slight variations in the spring tension could make a tremendous difference as far as cooling effect.

By such an approach it would be possible, I think, to test these key components and see how they work together at relatively little expense.

I no longer believe that the cooling has anything to do with return air from the power pistons. This made sense to me at one point but there really doesn't seem to be any indication that the air is recycled in such a way in the patent and in the interview with Neal's son he states that the air from the power pistons was simply exhausted back to atmosphere. That his father never found any way to recycle or reuse this air at all. It seems unlikely to me that his son was mistaken about this.

I wouldn't want to underestimate the possible cooling effect of the "throttling". From everything I've read about it it seems to be the key to getting gases down to extremely cold temperatures, potentially even down to the point where the result is actual liquefaction of the gas.

I suppose I could be wrong but this is the only explanation that appears to me to solve all the mysteries and fully explain the various reasons for and functions of all the elements in this engine.

There would certainly be some kind of RHYTHM or "frequency" or "pulsation" to the "pumping action" of the equalizer, as with any such pump, but I think such harmonic "waves" would originate at the equalizer itself. It would fall into some natural rhythm, but this would not be dependent on the pistons in the compressor or their arrangement or number or anything of that sort. It would be purely a result of the thermal changes going on within the equalizer itself. So I believe that a test using just one cylinder for "compression" or cooling and one equalizer would work as well as anything else.

[Tom Booth]

...
If the compressor cylinder pulls a partial vacuum, then when the upper valve opens, it seems the outside air would rush in quickly and equalize the pressure in that cylinder before the valve closes.  The discussion about gas particles moving fast and slow inside the cylinder, I do not think is valid, since any gas, even at low temperatures, contains fast moving gas particles, otherwise it would be a liquid.
...

It may be a moot point but I don't agree with the above statement: "the outside air would rush in quickly and equalize the pressure in that cylinder".

This disregards the extra pressure exerted by the valve spring which I think, in this case could be considerable.

In other words, there would have to be a rather strong vacuum before the valve would even open. When the valve did open it would not rush in freely and immediately equalize but would be "throttled", that is, severely restricted. I don't think there would be any equalization of pressure on the down stroke. There wouldn't be any equalization of pressure, I don't think, until the piston was rather far along on the return (upward) stroke. Finally, towards the top of the upward stroke the pressure in the cylinder would climb above the 15 psi atmospheric pressure and the check valve would open allowing the air to escape into the pipe leading to the tank.

At any rate, I have been discussing this point about the apparent "throttling valve" on one of the science forums to get some outside perspective on this Joule-Thompson throttling valve idea in relation to this engine that some here might find interesting.

One of the points raised recently there is that the Joule-Thompson effect could only account for a few degrees temperature drop.

IMO, this is not necessarily true as these sort of calculations are based on a one time event. That is, the release of some air through a valve or other throttling mechanism from one chamber into another. The temperature drop from Joule-Thompson Effect in such a circumstance is relatively insignificant. Perhaps only a few degrees.

My counter argument to that is that the situation in a running engine is quite different. For example, I cited this Wiki Article: http://en.wikipedia.org/wiki/Carburetor_icing

The pressure drop in an automotive carburetor at the throttle is relatively slight, I should think, compared with the potential pressure drop intentionally produced with a throttling valve as in the Neal engine, yet with continuous operation of the engine, the effect is, apparently cumulative, the result being, in a car engine, the icing up of the entire throttle body with the potential for causing damage to the carburetor or possibly a run away engine due to the throttle becoming frozen in position. "The inlet manifold and parts of the carburetor often have warm water from the cooling system or exhaust gas circulating through them to combat this problem."

http://www.scienceforums.net/topic/72398-help-needed-for-pvnrt-calculation/?p=731866

I don't really know at what RPM the Neal engine was supposed to operate, but supposing that there was a cooling effect of just 1 degree with the first down-stroke of the piston. This would presumably result in some cooling of the valve itself and the surrounding housing, the cylinder as well as the top of the piston etc. possibly to only an imperceptible degree. Very slight cooling. But then this is repeated over and over again. The cylinder might grow a degree colder with the second stroke and a degree colder with the third.

If the compressor were operating at just 300 RPM which is very slow compared with most engines (that might operate at several thousand RPM), The CUMULATIVE temperature drop could be quite significant in just the first minute of operation.

The reason I bring the reference to carburetor icing into the discussion is that this seems very similar to what might be expected with the Neal device as it involves a pressure drop in ordinary air through a throttling device from atmospheric pressure to some lower pressure in a continuously operating engine rather than in a more controlled "scientific" environment where air is simply throttled between two chambers.

What might seem like a relatively insignificant drop in temperature under carefully controlled conditions, could in fact, IMO, be highly significant in a situation where the effect is continuously repeated and cumulative.

[Joe1]

Thanks so much for the thoughtful comments.  I will study your insight and try to contribute to your theory.

[Joe1]

Hello Tom Booth,
I promised to find something to support your heat engine theory.  It has been 6 months, but here it is.  Hopefully this thread is still working.  Have you ever seen these three patents?  They all promise overunity performance. Warning, these are looooong patents, but there is much information contained within.  Took me a while to find them.

8268030 Abramov 2012
I like this one. He references Bernoulli, Coanda, De Laval nozzle, Ranque-Hilsch vortex tube. You must read closely, he is not spoon feeding, but the data is there. Smart guy.
column 21, lines 36-43
col 23, lines 7-12

7775063 Thompson 2010
column 23, lines 9-25

4624109 Minovitch 1986
This guy talks like a snake oil salesman, but he was awarded the patent.
col 1 lines 12-53
col 12 lines 26-44
col 20 lines 42-47

These line references are just to get you interested. Reading these will be a long journey, so much information, amazing. If a reader could learn these three, It seems a working model of an overunity heat engine would be possible.
Joe1