Self-filling air tank, new theory

[Lutherman]

Hi Chris

Thanks for your compliments. I am going through design changes pretty fast right now but I think I've settled on something. You're right, a separate driver could solve the problem, something not dependent on tank air. For now I have a new idea posted on the blog. I stopped on the heat-driven equalizer too since it seems the Kadenacy Effect requires the pressure in the equalizer to rise well above tank pressure so that when the contents of the equalizer exit into the tank, they ALL exit. Leaving the equalizer empty to accept the next batch of atmosphere. Well that goes against the whole idea, you don't want to have to make extra pressure.

The new idea is very straightforward, please take a look at the blog. Send me an email too, I get lots of it and senility is setting in. You don't need my permission to build my ideas, when I publish it then it can't be patented. I like to know what you find out though. No I don't think high pressure is needed for basic tests, it might be needed in a car just for storage so the tanks aren't too big. Hard to say at this point. But in a car you need enough extra storage to get over hills.

Some inventors said their device would work ONLY in a car, not in a stationary application. Food for thought. All cars are air compressors. Above 20 miles per hour the biggest energy drain is compressing the air that stands in the way.

Canned Thunder

Scott

[Peter Lindemann]

Back to Bob Neal

Scott,

This latest idea looks great. It may explain WHERE the full pressure air in Bob Neal's engine/compressor unit goes after it has produced the power stroke. This is the one piece of information that is not plainly evident from the patent. If the full pressure air is added back in at the equalizer, after the other air is put in from the compressor pistons, the total amount of energy required to put it all back in the tank at full pressure should be minimal.

Your new "downhill equalizer" looks like the most logical method to accomplish what Neal claims, but does not show.

I knew you'd figure it out!!!

Awesome.
Peter

[Lutherman]

revision is ready now

Thanks Peter, I'm happy to hear that you like it. I'm still working through the details, and the picture is better than the first draft I had posted to describe it. I re-posted a better description and as far as I know this configuration should work. I'll keep tweaking the spreadsheet and see if I can find anything wrong with it.

It seems to be capable of handling the loss of a full-pressure, non-expansive air engine (like a commercial air motor) with its wasteful exhaust of air that still is pressurized.

Scott
Canned Thunder

[everwiser]

What cycles the piston and what is the air pressure on the driven end in your example? Is the pressure on the rod-end of the piston = to tank pressure (88-90psi in your example)? I'm trying to wrap my head around what this equalizer/compressor stage is accomplishing. Thanks for any elaboration.

[ozmatic]

Hi Scott,
I checked out your new Downhill equaliser, and found a problem, unless I am missing something.
What happens in the space, behind [to the right] ,of the piston in the equaliser? This cannot be at atmospheric pressure or all advantage is lost -the compression stroke would be against full tank pressure. However, if this space is vented into the main tank, a lot of compression work would have to be done to admit the low pressure air, when the piston is moving from left to right.
I really hope I am missing something here, as this is very easy to build in a way that will allow experimentation.
I am still very interested in your surge driven equaliser, as it would allow me to test some ideas of my own. If I can find a low power way to get the equalised air back in the tank.
Chris

[Lutherman]

attempted elucidation

Hi and thanks for asking. Yes, a cheap way to test the idea, I've been looking for many years and I hope this is it.

The best way to run the two compressors is electric motors, since an efficient electric motor, I'm guessing, is a lot smaller and easier to come by than an efficient air motor. The drawing isn't finished, it should show that kind of thing.

On the right side of the piston the sketch shows a rudimentary representation of what is supposed to be a rod guide and some vent holes, as this non-working side of the piston is supposed to be open to atmosphere. Crankshaft or rack-and-pinion or some other way of making the piston go back and forth are not shown, but the power to do it should be about the same for air engine or electric motor. Massively simpler to use an electric motor, for anyone who doesn't already have an air engine. Who has an air engine???

The pressure on the left side of the piston (in the equalizer) goes from atmospheric (14.7 psia at standard conditions) to maybe 16 or 20 psia or so under the influence of the supercharger, also not shown. Then the big valve opens on the side of the equalizer and it goes up to about 88 psia. Then the booster works against a pressure differenctial of 90 - 88 = 2 psi.

I am hearing the objection that people think the two sides of the piston represent the pressure differential through which the piston does its work. I think this is a false assumption, so if someone has the knowledge and experience please speak up. I posted the more detailed answer on the blog.

According to the work equation and PV diagram for compression work, the pressure differential that the piston must overcome is not the difference on the two sides of the piston. If this were true, then a single-acting piston would be a total loser in any compressor, all compressors would have double-acting pistons. And look at the second, third, etc. stages in a multi-stage compressor. High pressure on one side of the piston, like a booster piston, and atmosphere on the other. Assuming single-acting pistons. Same thing, the back side of the piston is only compressing the earth's atmosphere an infinitesimal proportion.

No, I am sure, but please present an argument if I am wrong. The pressure differential that a compressor piston works against is the initial pressure of intake vs. the final pressure of delivery. That is fully backed up by standard work equations for compression. These equations have no term representing ambient surrounding air unless that air actually goes into the machine.

Right? I'll be back in a couple of days, please speak up.

Luther

[ozmatic]

I want to build this

Hi Scott,
I have been thinking about this for a few days, and this is worth building because it is a cheap, easy to build, vehicle for testing compressed air theories.
I am not a genius on theory - but I am very good at applying ideas to real life.
So, how about this for a set-up:
Plumbing pipe is the best way to do this, because the connections are easily available and cheap.
Main tank = 4" pvc pipe [ length to be taken advice on ] in future to be abbreviated to :TBTAO.
Equaliser = 1.25" pvc pipe
The glue for the endcaps to the pipes will determine the pressure that the system can operate.
I like pvc pipe because it has a low friction constant [TBTAO], so piston friction losses will not be a limiting factor.
The main tank/ equaliser valve will be a radio controlled solenoid that will admit tank air as fast as possible [ for my own agenda]. I can definitely handle the electronics on this.
The piston will be aluminium with a groove machined to take a ring [TBTAO]
I am probably one of the few people that has an air motor! - in fact I have 2 GAST 4hp air motors that I got on Ebay because they were listed as "generators - coils removed"!! [5$ each and a a lot of post got them to me].
I will use them if I can get a result from this test setup .But will go with electric compressors for the test set-up.
I need to collaborate with you on this- so shoot me down, or tell me to go for it!
Chris

[everwiser]

...

No, I am sure, but please present an argument if I am wrong. The pressure differential that a compressor piston works against is the initial pressure of intake vs. the final pressure of delivery. That is fully backed up by standard work equations for compression. These equations have no term representing ambient surrounding air unless that air actually goes into the machine.

Right? I'll be back in a couple of days, please speak up.

Luther

Unless I'm missing something...

You'll be putting more load on the piston and thus the eccentric/motor running it. Air will move from the booster to the main tank when the piston's compressing of the air in the booster reaches a pressure higher than the pressure of the main tank. With your 'equalized' pressure between the booster and the main tank, the pressure increase needed to move the air to the main tank from the equalizer/booster happens immediately and thus the motor is greatly loaded from the beginning and at a point in its rotation where it has to work hard to rotate the eccentric and push the piston forward. In addition, you're still only gaining the same volume of air as you would get without the equalizer since the volume of air that it took to raise the equalizer to main tank pressure came from the main tank to begin with.

If you had main tank pressure on both sides of the piston, then it would be less load on the motor.

[Lutherman]

Correction regarding compressing air by pressure equalization

Correction regarding compressing air by pressure equalization

Sorry to say, I have discovered a mistake in the way I was using the air compressor equation. Hold off on building it as it won’t work till a better configuration is found.

Compressors do three jobs.

1. Intake is negative work because the piston is already moving under power from the crankshaft and the intake pressure, whether atmospheric air or something else, enters on its own power and cancels the work done to move the piston on that stroke.

2. Compression is when the air trapped in the cylinder is being reduced in volume and increased in pressure.

3. Delivery is when the air has reached tank pressure and is being delivered to the tank at constant pressure.

Each of these three steps has its own calculation to find out the work in ft-lbs or whatever units you use. They can be combined into a single equation so the work of a standard compressor can be found quickly. That’s where I got it wrong. The combined equation is for standard compressors and this equalizing compressor is not standard. A closer look was needed, as prompted by some emails and forum messages, thanks to all for your input.

The calculation has to be done separately for each of the three steps with attention paid to what the calculation is trying to do. My mistake was to assume that the equalized pressure was the intake pressure on an intake stroke. It is not. The piston is not moving when the tank air enters, it has already had its negative work intake stroke done by atmosphere. The extra pressure then becomes an extra load that has to be pumped laboriously back into the tank. The good news MIGHT be that it doesn’t actually have to go into the tank, so forget that load and just use the air. The problem is still that a lot of tank air is used to compress a little atmosphere. So more creative work is needed. Take a look at how Bob Neal did it, and ask yourself why he needed a 28 cylinder compressor. Also look at Hudspeth & Lunsford’s patent and Baruch & Isaac Leibow’s patent.

I could go into more detail but the point is made. The idea can be re-thought-out since compression by equalization is free of losses and since any atmosphere brought into the system is external energy. I have switched my focus for now to a different concept that was patented in 1892, and is by now in the public domain. It will be featured in my upcoming book Air Car Hall of Fame, and in the meantime I am going to try to get the math right before I say it will work.

Luther

[Schpankme]

Compressors do three jobs.

1. Intake is negative work because the piston is already moving under power from the crankshaft and the intake pressure, whether atmospheric air or something else, enters on its own power and cancels the work done to move the piston on that stroke.

2. Compression is when the air trapped in the cylinder is being reduced in volume and increased in pressure.

3. Delivery is when the air has reached tank pressure and is being delivered to the tank at constant pressure.

Luther,

I was under the impression that you would be tracking four (4) variables.

1) Intake of atmosphere (negative work)

2) Compression of atmosphere

3) Power stroke

4) Exhaust stroke (negative work)

Schpankme

“Live in the sunshine, swim the sea, drink the wild air…” - Ralph Waldo Emerson

[Lutherman]

how many cycle events

Your list looks like a four-stroke engine. This is a special kind of compressor, not an engine. So it has no exhaust, it does have a delivery to tank.

Which reminds me, the four-cycle air engine is probably as close as we can get to the equalization engine. The injection of tank air has to do negative work--in a compressor that is a part of the cycle that helps turn the shaft or cancels any shaft work that is done.

I have a thing on the 4-cycle air engine linked from the home page at air car access .com, I'll have to re-read it. I need to get busy and finish my next book compilation, there are 169 air engine inventors screaming at me from their grave, they all want to be remembered. "Air Car Hall of Fame" is on its way.

Luther

[lancashire lad]

why try to reinvent the wheel

glad to join the discussion.
I have read many of the threads on this subject the Neal compressor,
The drawing is incompleat, because it does not show the bottom half which has an inlet and an out let both with non return valves fitted. The neal compressor is basically just an air cylinder, if you fitted a quick exhust to each port that is it finished. the hollow tube with the non return valves is just the free air feed for the top half of the cylinder.if you look on the cylinder block it has no inlet but does on the bottm half.
also it shows a lubrication port to the cylinders so the point about oil in the cylinders appears not to apply to this design. there is a simple way to double the air pressure that is feed into the tank, useing a pressure booster. if you had the seven cylinders lined up there probably would be some sort of compresion say this was 2 (30psi)bar it would double it to four bar (60psi)and compressed again would be 8 bar (120psi).
because you are compressing seven atmospheres (seven cylinders)I cannot think the tank will reach more than this 7x15 approx equals 105 psi. if you take 200psi out you would requier 14 cylinders not the seven per drive cylinder the patent shows.
when testing tanks you pump them with water to twice the the pressure they are going to hold in this case 200 psi. Is this a mistake people are reading to much into that it runs at 200 psi. and that the referance to this tank pressure is just that it needs to be cabable of holding 200psi.
the air exhaust of the drive cylinders maybe capable of some work as they pass to atmosphere, i have certainly used this to change over valves etc but may be capable of even more.
has anyone actually set up the seven cylinders to see what they produce and the to one drive cylinder (14 for two drive cylinders) it seems to be the obvious place to start. it also says the air in the recievers are at freezing point and heated up just before the drive cylinder which are also double acting cylinders, the bottom of one and the top of the other driving at the same time. why try to reinvent the wheel if this patent works.
sorry got to dash off, no time to re read and edit, but here goes for my first attempt got loads of ideas bouncing around in my head will try to test some of them. I have worked with pneumatics all my working life.

[lancashire lad]

why reinvent the wheel

sorry I had to dash off to a meeting on last post and did not want to lose what had been writen , on last thread. and just noticed the spelling mistakes but that probably will not get any better.
the last point is that on the drawings it shows the equaliser as number 50 on the drawings which is the whole of the cylinder block. as the compresor cylinders are runinng on an eccentric cams the passage of the piston is not even, being quickest in the middle section. and slower at the top and bottom.( The only way to get even pressure would be to have a heart shaped cam.) but by having the 14 cylinders pushing and pulling at different times of their cycles this would equalise and balance the pressure so you would not have high pressure stages. also with the rod being in one side of the cylinder both sides of the cylinder would not be producing the same amount of air(volume)this also would be equalised and balanced along the bank of 14 cylinders. so there would be no high pressure spots and a smooth action. It all looks very clear to me, I am not afraid to be totally wrong but I believe the equaliser everyone talks about is the whole of the compression block. and not refferance to some other valve. if this is not the case why not have just 2 big compresor units 7 times bigger than each of the drive cylinders, because it would need to much energy to move it and unequal compression rates.
We are all here to add what we can and I would welcome any comments on these 2 quotes. our aim is for the same thing. success.
some how a small model needs to be built not a car just like the patent to prove the patent. but using modern off the shelf parts. the only special part being the cam.

[sebosfato]

You should consider where energy is coming from.

If is from ambient temperature, you need to find the right deal of energy density (compressing media) and energy absorbing (expanding) incompressible media. Note that must be different materials in order to be able to trap ambient energy with efficiency.

For example if you use air only as it robs the energy from the ambient it will expand but the air being robed will compress, canceling a bit the effect even if it is already pronounced producing an explosion.

explosion = rapid expansion

What i'm saying is that a pure air motor won't be too efficient to run only on ambient energy.

You must also consider the ideal manipulation of intake and exhaust valves.

You don't need to refill any compressed air tank, if you succeed in to find a media that is abundant and have those proprieties, and thus is useable as a energy transfer media, possibly light in weight, non toxic, and free, like water that come from the sky.

Said that is only about experimenting.

I want to experiment my self but as i'm not able for time and money questions, i gave you the set.

try it, experiment,
than tell me if i was right.

=)

Fabio