Rotary Piston Engine

Okay. Good for you.

I presume you don't have data to support this claim because the seal problem, though much improved, still lingers.

I applaud your enthusiasm and confidence. Go get 'em.

Yes I do have some data, based on compress air efficiency that is 72% @120 psi using custom 5" ring seals and 1"x2" vane seal.

That is less then 2%-5% of combustion when using fuels.

I used a small engine to compress air/fuel mixture into the external combustion chamber.

Your data looks more like unsubstantiated results rather than anything one should brag about. Having somebody verifying your measurement techniques (metrology) and calculations will go a long way. Better yet will be to have them to perform their own tests on the new engine design with their instruments.

Here's an approach you might try to make realistic data with this design. From the apparent size (judged by spark plug dimensions) the power of this engine is probably in the range of a small electric generator engine, ~2000W. Measure the amount of time a COTS 2000W generator can power 1000W of a resistor load (space heater) with a cup of gasoline. Then replace the ICE engine with your new engine and power the same load and only one cup of gasoline and compare running time.

It is difficult to visualize the seal problem from the patent drawings, esp without the parts key right at hand. As we see for 4 stroke internal combustion engines, a set of simplified diagrams showing the combustion stages and the component positions at each point would make it easier for someone to get an idea of the forces on the seals. We can find Wankel engine cycle diagrams, for instance, and see what the major components are.

The posted image is too small to read. I can't see anything in it that looks like a piston, nor anything that looks like rotary. Conceivably the write-up explains this, but it too is unreadable.

Do you have a link or other scheme that actually gives any useful information?

https://patents.google.com/patent/US6860251

That didn't help even a tiny bit. The images were even harder to see than before, and the write-up was unspeakably terrible.

Evidently this thing has been around since 2004, with no apparent progress since then.

That doesn't explain even a single damned thing, Buferd.

For instance, what is item 50? A bolt with threads that don't engage anything whatsoever? JHFC, how can anyone be so wretchedly dumb as to buy into this nonsense?

So , can I put you down for 2..?

No, but thank you for clarifying about who would fall for it.

This would have made a great "What is it?" picture....

Maybe, or maybe not, but what in hell does this have to do with my post?

Whaddaya mean would have?

I have read all the posts here, and I still have absolutely no idea what that image depicts.

Is it another candidate for the museum of unworkable devices?

Glad you also found this useless. Thought I was being dumb not understanding.

How did anyone grant a patent based on those drawings?

Well it appears to be a lawnmower engine that is supercharged by another lawnmower engine ...

Is this anything like the rotating rocket engine...?

World-first "impossible" rotating detonation engine fires up

https://newatlas.com/space/rotating-detonation-engine-ucf-hydrogen-oxygen/

This will be great if they can scale it up and get it right.

Still needs a lot of testing, but yes looks very promising...I love it when guys do the impossible....

https://en.wikipedia.org/wiki/Dragons%27_Den_(British_TV_programme)

"Shark Tank"?

"Had problems with the seals"

Have you thought about great white sharks?

Sorry, couldn't resist.

Ruuun Forrest,, RUN !!!

Mr. Reed has put a lot of effort into it, based on the patent application. Unfortunately for him, it lapsed 7 years ago. I read through the papers and had no difficulty in reading it or seeing the drawings at any desired magnification. Perhaps Tornado needs to use a computer with a decent monitor instead of a smart phone.

The overall impression I get is that the engine has a large number of moving parts, which can cause mechanical losses and increased problems with seals, etc. Also, it appears to have a fairly large mass, but that may be a completely erroneous observation. In that regard, a Wankel type engine has very few moving parts and a very low mass compared to its output power--I say this from personal experience with an early RX2 car. It did suffer from lower efficiency than I would have expected or desired. Perhaps that is the reason why Mr. Reed has done his work.

--JMM

You are mistaken about the smart phone. My monitor is an Acer P215H with good enough resolution for AutoCAD™.

On a second reading of SE's post of the patent, I found some image manipulation features that were not immediately apparent. That solved the visibility issue.

I agree about the very large number of parts.

The drawing and design was my own, detail to get a good understanding what it is.

I realize that having a external combustion chamber has it's benefits, almost like a combustion chamber in a jet engine. The big difference is compressed air enter into the chamber at 150psi that is sealed with a special valve, at combustion the timing release the expanding gases to drive any type of mechanical device. the patent is the combustion chamber, not the engine.

The engine was used just to compress air/fuel. The combustion chamber is to drive the rotary.

On what grounds would this ever be the most efficient engine ever built? I don't see any energy cycle data in your deficient literature, not even Carnot efficiency.

Efficiency is much more then moles and air flow.

I'm studying this field with, " The Internal combustion Engine in Theory and Practice". by Charles Fayette Taylor.

Heat is where all this energy is transfer into mechanical work. A piston type engine is not efficient, 22%-25% average, due to expanding pressures and mechanical conversions where most of the energy is release.

The rotary design allows a complete 250deg power stroke, unlike a 2/4 stroke engines where most of the power is at 90% of the crank shaft.

This is my design verse a standard piston engine drawing, even a cave man could figure that out.

This is just the torque on both engine at stall, the rotary did more work with 217.5deg vs 90deg of a 4 stroke engine.

My design would take less energy to produce more mechanical work.

(4 stroke) 90deg power stroke vs (rotary piston) 217.5deg power stroke.

As Tornado and I point out, your claims are not substantiated. Denigrating your critics by comparing our free insight with cavemen does not help your position.

To suggest I'm calling both of you cavemen, is just you over reacting.

My drawing was simple, even a cave man can understand.

Maybe it's best you move on, don't want to offend you being so sensitive.

Some of the past comments are a bully tactics, but clearly I'm not offended,

Common sense with mechanical work speaks for it's self, but some people can't grasp that.

Have a wonderful day.....

Truth..,

A minor correction. The 3:1 ratio on a Wankel engine has the output shaft rotating three times for each rotation of the rotor, not the opposite.

--JMM

Good catch. Thank you for the correction.

The concept of <...Maybe it's best...cavemen...move on...> is at odds with the concept of peer review, which seems to be the reason for the existence of this thread.

So far, peer review has achieved little other than <...offend...>. Maybe the style of the message is in need of improvement, perhaps?

First, I definitely do like the concept of eliminating reciprocating motion from engines, so the initial thought of your rotating vane (I refuse to call it a piston) is good. Also I definitely commend you for actually constructing a prototype.

But! You now have the reciprocating "door" that must move out of the way each time the vane passes and then quickly close again. That's definitely a problem.

I have read a fair portion of the patent document and studied a few of the drawings, so I think I understand how the device is intended to work, but there are too many details not addressed, and some definite inconsistencies. At one point you mention a microprocessor-controlled timing of the ignition spark, but then you proceed to describe what sounds to me like a standard magneto system.

Probably the greatest flaw is not considering the energy required to compress air and fuel. Both of these processes are external to your "engine". Likewise, the external combustion chamber is a real energy sink. No matter how carefully you craft the passageway for the combustion products from the combustion chamber into the working chamber, there will be considerable reduction in pressure as the mixture follows this path.

Gasoline burns much too rapidly to work well in this engine; you need a fuel that will continue to burn for a large fraction of that 250° rotation. Gasoline would provide a burst of pressure at ignition, but the small pathway for that expanded mixture to enter the working volume will greatly reduce that pressure.

Finally, your "caveman" drawings are very misleading, because the two drawings are not to the same scale. Your 3" diameter piston is shown very nearly the same size as the 8" outside radius of your rotary vane.

Thanks for trying, but I don't see this as workable.

The two types of engines are different, but the same amount of displacement are identical.

Instead of doing the math and insult anyone, I did it and that's the same travel volume.

I do agree with the piston gate, that's also why I built my design like this.

This design works much better, this is how the updated build was.

This is a single vane motor, but you could stack them to gather with a off set of 90deg to make a 4 vane motor

I presume the downward-pointing arrow represents the combustion mixture passing from the external combustion chamber into the working volume. That opening is nearly sealed off from the working volume by the rotating cylinder, so the mixture can't really get in to the working volume! It's difficult to tell what's what in this drawing; but I presume the black rectangle at the bottom is the vane, and the black rectangle at the top is a seal. What happens when the vane hits the seal?

I think I've wasted enough of my time going down this rabbit hole! I'll keep watching, in case you come up with a real practical innovation.

Yo, Thag--why wheel no turn?

Your drawing is massively deceiving!

Here is the drawing with the rotary engine shown at the same scale as the piston engine (using the dimensions given on the drawing of the rotary engine):

I don't know how you calculated the working volume of your rotary engine, but the calculation is way off, unless I totally misunderstand the engine drawings!

did I make a mistake?

the vane surface is 1x1x2= 2cu/in

a. = (8"dia. area ) pi(r^2)=50.265482246cu/in

b. = (7"dia. area =pi(r^2) =38.49451001cu/in

c. = a/b=11.77097224cu/in at 360 deg rotation

d. =c/360=0.03269714511cu/in per degree

e. =d*2" = 0.06539429022 (2" width)

14.14/e =216.23 deg.

I believe your area calculation is off. (pi*r^2)= 402cu/in?

pi * (4^2) =50.265448246 cu/in

Here are your new mistakes in this post:

1. The vane area is just 1 x 2 = 2 in², not in³.

2. There is on such unit as cu/in, anyway.

3. In your original drawing, the 8" and 7" are radii, not diameters.

4. From there on, everything is wrong.

I see some of my questions, going back and forth I did make a few mistakes.

The 2in stroke was off and should have been 1.5in and 3" would be the complete stroke as Tornado mention.

I was going to calculate 7.5" instead of 7" for torque, but wanted to see if anyone understand that, yes I was going to bring this up!

Someone numbers was way off, I know we all make mistakes.

I wasn't the only one who made mistakes, but at the end of the day my calculation was correct!

The exhaust port is in Fig. 4A 16, It is far greater then the intake.

My calculator is a Casio Fx-115 ES and did on purpose added all the extra 9 decimal numbers because some people needed it.

"When people get into details, they make mistakes and never end up building nothing"

"...added all the extra 9 decimal numbers because some people needed it."

NO! It is indeed a good idea to include one or two extra digits in intermediate calculations, rounding off the final answer to the appropriate number of digits. No one needs anything beyond that.

Absolutely true that we all make mistakes, but please use correct English! ("...never end up building nothing") [double negative]

Unless your "Engine" can power its own compressor and pumps, it isn't an engine, but an add-on to another engine.

Once again, I commend you for trying, but I'll be flabbergasted if this goes anywhere.

In addition to dkwarner's notes, here are some of your other mistakes:

Areas are expressed as in², not inches (e.g. ~7.07 in² for area of 3-in circle).

If the piston stroke is only 2 in, the crank won't even go around.

The crank arm is visibly shorter than the piston radius, even though both are supposedly 1.5 in. Inaccurate drawing or labeling.

Torques are not expressed as lb/in (which reads as pounds per inch); the correct units are lb-in (which reads as pound-inches). Your torque numbers are good, though, just not the units.

Your right, I should have wrote it down right.....

I wasn't making a perfect drawing,either.

My mistake, it won't happen again!

The whole point of posting though is for the <...caveman...> to review. If the <...caveman...> verifies the outcome, then the design is solid. That's the principle behind peer review.

This thread didn't get that far.

The problem with peer review is that for any doofus who dreams up a goofy idea, his/her peers will also be doofuses. Instead, the proper standard is competent critical review, which is quite rare.

Indeed.

The <...cavemen...> correlation is astonishingly rude.

If others want to build something and post it for peer review, then the correct vehicle for this is a different thread.

This thread, however, is about the <...Rotary Piston Engine...>. Please keep this thread "on topic".

Since your post #50 was not in reply to any specific other post, I have to assume that you are talking to/about all of those here.

Yes, many of us here are are old enough to be partially or completely retired, but don't forget that "old" also means "experienced". Most of us here are here because we want to help others solve problems. Each of us has had a different set of experiences; together, we can help solve many different kinds of problems. As you can see if you look, I've been doing this for fourteen years.

You want to see something we've made. Here is a machine I made, entirely by myself, in my own garage, with my own tools, almost exactly 20 years ago. The photo was taken with the first digital camera I had available, so isn't of high resolution:

I won't give any details, but it it did the required job!

I think I've read all of the posts in this thread, and I don't remember any that could be described as "bully tactics".

Whose math skill are off? Some of my calculations didn't agree with yours, because they were based on the incorrect dimensions of your drawings.

I probably should not have responded to your post at all, and I won't respond to the rest of your rant.

This post was deleted because it was an attack on another user. Please review the Site FAQ and the Rules of Conduct.

My most "fantastic" build consisted of 17 piping systems totaling about 35,000 feet in a fish processing plant on Akutan Island, in the Aleutians. Much of it was bent piping rather than elbows. I devised a 3-D vector system using determinants and the laws of sines and cosines to calculate bend angles and rolls between successive bends. (Too bad I never commercialized that.)

Over the years I have fabricated a number of mechanisms. Most are prior art, hence not inventions, but the craftsmanship is pretty good.

Your comments on dkwarner's device are insulting. So who's the bully?

There is obviously a breakdown in communication here. The information might not be received in a way that makes its value clear up front.

Dunning & Kruger did an informative study that would be a useful reference to keep handy (for anyone unfamiliar with the style of explanation typical of an inventor of your experience and mindset) when reviewing your introduction to your work. Familiarity with Dunning Kruger is an excellent tool that can unlock the true worth of many ideas of individuals who refuse to be trapped by the values touted in an imagination crushing 'standard education'. The type that gives reverence to widely accepted standards.

It does seem your passion has allowed you to get sidetracked with comments that don't seem to be what you came here for. You have overlooked a couple comments and left those unanswered.

Specifically I left comment #41. I'm calling for you to back up your claim about a longer power stroke being correlated with higher efficiency. Alternately, perhaps you could posit other ideas about why you feel this could be the most efficient engine ever created.

That sound like a good question.

I will clarify instead of getting off track.

I don't understand much of what the OP has said, but certainly in the marine diesel engine field a longer stroke does improve efficiency. Cant see it being any different in other engines.

"Simple geometric relationships show that an engine cylinder with longer stroke-to-bore ratio will have a smaller surface area exposed to the combustion chamber gasses compared to a cylinder with shorter stroke-to-bore ratio. The smaller area leads directly to reduced in-cylinder heat transfer, increased energy transfer to the crankshaft and, therefore, higher efficiency."

Do you have a source for that quotation?

IIRC, for a cylinder the largest volume-to-surface-area ratio occurs when the diameter and height (or stroke) are equal; i.e. "square".

Don't know what IIRC stands for, but there are many "sources" on google. You can get more power out of a square or even over square engine, but not more thermal efficiency. However, there are many other considerations, amongst them the increased size of the engine with the longer stroke and the higher rpm of the lower.

From Wiki

Oversquare engine examples[edit]

Oversquare engines (a.k.a. "short stroke engines") are very common, as they allow higher rpm (and thus more power), without excessive piston speed.

Examples include both Chevrolet and Ford small-block V8s. The BMW N45 gasoline engine has a bore/stroke ratio of 1.167.

Horizontally opposed, also known as "Boxer" or "flat", engines typically feature oversquare designs since any increase in stroke length would result in twice the increase in overall engine width. This is particularly so in Subaru’s front-engine layout, where the steering angle of the front wheels is constrained by the width of the engine. Although oversquare engines have a reputation for being high-strung,^{[citation needed]} low-torque machines, the Subaru EJ181 engine develops peak torque at speeds as low as 3200 rpm.

Nissan's RB, VQ, VK, VH and VR38DETT engines are all oversquare. Additionally, SR16VE engine found in Nissan Pulsar VZ-R and VZ-R N1 is an oversquare engine with 86 millimetres (3.39 in) bore and 68.7 millimetres (2.70 in) stroke, giving it 175–200 horsepower (130–150 kW) but relatively small torque of 119–134 pound-feet (161–182 N⋅m; 16.5–18.5 kg⋅m)

Extreme oversquare engines are found in Formula One racing cars, where strict rules limit displacement, thereby necessitating that power be achieved through high engine speeds. Stroke ratios approaching 2.5:1 are allowed,^[a] enabling engine speeds of 18,000 rpm while remaining reliable for multiple races.^[4]

The Ducati Panigale motorcycle engine is massively oversquare with a bore/stroke ratio of 1.84:1. It was given the name "SuperQuadro" by Ducati, roughly translated as "super-square" from Italian.^[5]

The side-valve Belgian D-Motor LF26 aero-engine has a bore/stroke ratio of 1.4:1.^[6]

Early Mercedes-Benz M116 engines had a 92 millimetres (3.62 in) bore and a 65.6 millimetres (2.58 in) stroke for a 3.5 litre V8.^[7]

Undersquare or long-stroke engine[edit]

An engine is described as undersquare or long-stroke if its cylinders have a smaller bore (width, diameter) than its stroke (length of piston travel) - giving a ratio value of less than 1:1.

At a given engine speed, a longer stroke increases engine friction and increases stress on the crankshaft due to the higher peak piston acceleration. The smaller bore also reduces the area available for valves in the cylinder head, requiring them to be smaller or fewer in number.

Undersquare engines exhibit peak torque at lower rpm than an oversquare engine due to their longer crank throw and high piston speed.

Undersquare engines have become more common lately, as manufacturers push for more and more efficient engines and higher fuel economy.^[8] Undersquare engines have a higher volume/surface area ratio,^{[further explanation needed]} leading to reduced heat loss and higher BSFC.^[9]

https://www.acronymfinder.com/-IIRC-.html

The Wiki article says "Undersquare engines exhibit peak torque at lower rpm than an oversquare engine due to their longer crank throw and high piston speed".

Maybe peak torque at lower rpm is correct (I wouldn't know) but the idea that higher torque is given by longer crank throw is a common misconception. For a given cylinder volume and gas pressure, torque is independent of bore/stroke ratio.

"Undersquare engines have become more common lately, as manufacturers push for more and more efficient engines and higher fuel economy.^[8] Undersquare engines have a higher volume/surface area ratio,^{[further explanation needed]} leading to reduced heat loss and higher BSFC.^[9]"

Volume/surface area ratio is maximum when square, as can be shown by basic calculus. It's not clear why reduced heat loss would be an advantage. Rejected heat has to be disposed of, and what doesn't go out with the exhaust gas goes through the cylinder walls or overheating of the piston and cylinder would result. Also BSFC refers to fuel consumption so is lower when efficiency is higher.

My comment concerns efficiency, nothing to do with torque. Reduced heat loss means that it is "not a loss" - hence more efficient.

I was just commenting on the Wiki article.

As I'm sure you know, heat loss cannot be reduced at will. The engine is (presumably) designed to be as efficient as possible with the techniques and materials available. That then determines the quantity of heat rejected, which the cooling system has to deal with.

Tornado, what you say is true, but remember that the highest temperatures (and therefore greatest delta T and heat transfer) occurs near TDC.

While a 'square' set up has the least surface area per average volume of the cylinder, to get the least surface area per volume when it is most important (near TDC) an 'under square' set up is required.

That is very true, at TDC the heat produce is the maximum pressure that can't produce any mechanical work in a IC engine.

As the piston moves downward, pressure decrease while converting this into work. Only at 90 degree of a crank shaft is where the maximum power output is being produce, while pressure decrease exponential.

I'm working on the formula, but I must find a basic molecule of heat in gasoline.

If Gasoline has a average of 125,000 BTU's or 3785.412cc

The required formula for the calculation of the moles of gas is given below.

PV=nRT

Where,

• P is the pressure.

• V is the volume.

• n is the number of moles.

• R is the gas constant.

• T is the temperature

The value of gas constant is R=0.0821

What is the true answer of heat energy produce from 1cc of gasoline.

33 BTU for 1 cc?

Does 1 BTU heat air volume the same as 1 pound of water 1 degree?

I believe I need all this input to show if the rotary engine is more efficient with same amount of fuel.

If average TDC psi is around 1,500-1,800 psi, how much fuel was used?

"What is the true answer of heat energy produce from 1cc of gasoline. 33 BTU for 1 cc?"

That's about right. Gasoline and similar hydrocarbons have calorific value 44MJ/kg, and gasoline SG ~ 0.8.

"Does 1 BTU heat air volume the same as 1 pound of water 1 degree?"

No. Specific heat of air at constant pressure is ~ 1000kJ/kg/K ~ 240BTU/lb/°F. And for air volume you need the density, which varies with pressure and temperature.

I don't think calculation will give your engine efficiency with any confidence. The only way IMO is to build and test it. Good luck!

Thank you....

I agree that a prototype is where you would get a more accurate result.

How about if I base it on just combustion chamber psi with the same amount of volume; like a small single piston engine vs a rotary, would that give enough input data to compare the efficiency?

I realize formulas can only answer the possibility, but it would give some indication of efficiency would it not?

I was under the impression the the device pictured in post #2 IS your prototype.

If it is, then have you had it running? Since you mentioned using a separate engine to power the compressor, I assumed that you have...

If you have had it running, have you had it connected to a dynamometer (or other appropriate device) to measure the power output? And of course you must independently connect that compressor engine, under similar conditions, to a dynamometer (or other appropriate device) to measure its output, then subtract that power from the combination power output to determine the power added by your device.

I didn't have enough compression due to the combustion chamber size, it needed more compression strokes to get it to a combustion point.

So, I'm working on a simpler design.

That's also why the rotary design had 4 piston to pump the volume and compression needed for the combustion chamber.

Then you have wasted everyone's time on an already abandoned design version.

...and for that:

<unsubscribes>

If you ever come up with something that works, please start a new thread. Till then, good luck!

The OP wasn't talking about under square or over square engines and being over square or under square has no effect on the portion of the full cycle that the power stroke comprises.

I do agree with you that having a longer stroke relative to bore can improve efficiency because when at TDC, the surface area to volume ratio will be less than something with the same displacement engine with a shorter stroke relative to bore. That however wasn't the claim.

Less surface are to volume at combustion also does not appear to be a characteristic of the engine design discussed here. It would appear to have a rather thin flat combustion area that traverses additional surface as it compresses and expands as the seals both cover and uncover new bounding surface.

What's this nonsense about "liberals"? Nothing in this thread so far has been about politics, so that is just irrelevant (and inaccurate) name-calling on your part.

<...math skills is off, it was flat out wrong...>

Having scanned this thread several times it is proving difficult to see where any calculation is displayed that might attract comment, let alone critique.

The local optician's shop is closed at the moment owing to a virus outbreak. First impressions are that going there for an eye test won't make much of a difference.

In that case, assuming the ambient temperature is the same across the new engine and an existing one, its operating temperature must be much higher, and in the case of the claim of its being the <...most efficient engine ever built...> would be the highest in one yet.

Some testing data would be of value to support the claim.

It ain't rocket science: shaft power out, divided by combustion power in.

.

Simples.

First comment - what a technically good one.

Welcome, hope you have the patience to stay.

I agree with The Prof! Welcome to CR4!

> For those interested in the field of unconventional engine concepts I recommend heartily Douglas Self's website:

http://www.douglas-self.com/MUSEUM/POWER/unusualICeng/unusualICeng.htm

What a fantastic resource! Thanks for sharing it!.