Henry Yunicks Red Hot Vapor Engine Re-Creation

[DeltaV]

The Bourke engine that you rebuilt and sent to another group for testing, will they do dynamometer testing and record the torque versus rpm?
I would be very interested in the results.

Yes, they will do dyno testing with all the torque and RPM curves.

Interesting analysis on the use of an external supercharger. The double acting engine that I'm considering would actually have a short piston, and use one set of Schnuerle ports to feed both sides of the double acting piston. This was done to reduce overall cylinder length/height.

"The only difference is the supercharger is doing it externally with much higher parasitic losses." - Why does pumping air externally inherently have a higher parasitic loss? I genuinely don't know the answer and am curious. I know a lot of 2 stroke engines VE is only about 55% on average.

 

[pmuller9]

"The only difference is the supercharger is doing it externally with much higher parasitic losses." - Why does pumping air externally inherently have a higher parasitic loss? I genuinely don't know the answer and am curious. I know a lot of 2 stroke engines VE is only about 55% on average.

The two stroke engine is using the piston that is already there for pumping with no additional components or frictional losses.
The pumping loss is the majority of the energy losses.

Once you add an external device, you add the frictional losses from the drive system for that device and the friction of the device itself.
Along with that you add the very high energy losses due to the very low adiabatic efficiency of the supercharger.
As I showed you from the compressor map the of the TVS 180, it will be operating over the region that has efficiency from 20% to 65% as the supercharger pressure varies from a pressure ratio of 0 to 2. (This refers to the discussion in post #160 as to why the pressure varies)
That is a very high energy loss to be adding to the engine.

IMO it would be more efficient and less total package size to have a larger volume single combustion chamber per cylinder engine than a double combustion chamber cylinder engine with a supercharger to make the same power.

The piston port two stroke VE depends on the ability to fill the crankcase volume under the piston combined with the compression ratio under the piston to create as much transfer velocity as possible to fill the volume above the piston thru the transfer ports.

Rather than creating a crankcase vacuum as the piston moves towards TDC and supplying a short duration for the vacuum to draw in the intake charge as the bottom of the piston clears the intake port, I found that it was better to allow intake during the entire upward stroke of the piston and use either a reed or a rotary device to close off the crankcase during the crankcase compression period.
The cylinder fill, dynamic compression ratio and engine torque was greatly improved.

 

[DeltaV]

The two stroke engine is using the piston that is already there for pumping with no additional components or frictional losses.
The pumping loss is the majority of the energy losses.

Once you add an external device, you add the frictional losses from the drive system for that device and the friction of the device itself.
Along with that you add the very high energy losses due to the very low adiabatic efficiency of the supercharger.
As I showed you from the compressor map the of the TVS 180, it will be operating over the region that has efficiency from 20% to 65% as the supercharger pressure varies from a pressure ratio of 0 to 2. (This refers to the discussion in post #160 as to why the pressure varies)
That is a very high energy loss to be adding to the engine.

IMO it would be more efficient and less total package size to have a larger volume single combustion chamber per cylinder engine than a double combustion chamber cylinder engine with a supercharger to make the same power.

The piston port two stroke VE depends on the ability to fill the crankcase volume under the piston combined with the compression ratio under the piston to create as much transfer velocity as possible to fill the volume above the piston thru the transfer ports.

Rather than creating a crankcase vacuum as the piston moves towards TDC and supplying a short duration for the vacuum to draw in the intake charge as the bottom of the piston clears the intake port, I found that it was better to allow intake during the entire upward stroke of the piston and use either a reed or a rotary device to close off the crankcase during the crankcase compression period.
The cylinder fill, dynamic compression ratio and engine torque was greatly improved.

Interesting, I will take this strongly into consideration for future designs. What are your thoughts on opposed piston 2 stroke engines that rely on an external supercharger, such as Achates Power's 2 stroke diesel and the old 2T detroit diesels? Do they have the same issue? This is a direction I would like to move towards for future designs.

 

[pmuller9]

I was touring a small WW2 submarine that is parked on land in Mobile Alabama.
To my surprise and delight the cutaway view of the engine showed a twin crank, opposing piston, two stroke diesel engine with a supercharger.
I was thinking that without a cylinder head and valvetrain, how quite the engine would be for such a purpose. Perfect.

I always like the idea.
It has much better scavenging with the intake ports at the opposite end of the cylinder than the exhaust ports.
There is no cylinder head to dissipate thermal energy.

I would use a more efficient supercharger than the roots style.
The Screw and Auger arrangement that compresses air down the length of the rotors have one of the highest Adiabatic and Volumetric efficiencies. (Whipple/lysholm supercharger).

If you keep the Scotch Yoke, the supercharger can be replaced by cylinder pumping below the piston once again.
The non-cylinder side of the yoke could have the supporting shaft simply reciprocate out the other side of the crankcase.

 

[DeltaV]

I was touring a small WW2 submarine that is parked on land in Mobile Alabama.
To my surprise and delight the cutaway view of the engine showed a twin crank, opposing piston, two stroke diesel engine with a supercharger.
I was thinking that without a cylinder head and valvetrain, how quite the engine would be for such a purpose. Perfect.

I always like the idea.
It has much better scavenging with the intake ports at the opposite end of the cylinder than the exhaust ports.
There is no cylinder head to dissipate thermal energy.

I would use a more efficient supercharger than the roots style.
The Screw and Auger arrangement that compresses air down the length of the rotors have one of the highest Adiabatic and Volumetric efficiencies. (Whipple/lysholm supercharger).

If you keep the Scotch Yoke, the supercharger can be replaced by cylinder pumping below the piston once again.
The non-cylinder side of the yoke could have the supporting shaft simply reciprocate out the other side of the crankcase.
Even if the supercharge is kept, the Scotch Yoke sinusoidal piston motion has a much higher dwell time at each end of the stroke than the the conventional connecting rod/crankshaft configuration, which allows high port duration without sacrificing the dynamic compression ratio by using higher ports.

I'm now of the opinion that the scotch yoke mechanism is only useful for small displacements 1100 cc or smaller. Last year I conceived of a radically, and I mean radically, new method of transducing reciprocating into rotational movement. I unfortunately cant disclose how this mechanism works until I receive my patent that I filed for it. But it is an opposed piston uniflow scavenged 2T fickett-jacobs cycle, with only one giant massive cylinder, no crankshaft, and no connecting rods, and the pistons spin in the giant cylinder. The real beauty is that it exploits the square cube law, an 8" bore with each piston moving 4.5" downward gives a 9" effective stroke, which is a displacement of 452 cubic inches. The nominal dimensions of this engine without the supercharger would be approximately 9" in wide, 28" long, and 12" tall. A 1250 cubic inch engine would be 13" wide, 20" tall, and 51" long. This new engine morphology completes two power strokes per revolution. There is only two pistons, a spinning shaft, and bearings. The design came to me, of all things, during my one and only DMT trip in July of last year. I will have to build it and test it, of course, but I think it has the possibility of being the paragon of internal combustion, without compromise. Doubling the size of a cylinder increases its volume by a factor of 8, whilst only increasing surface area by a factor of 4. Larger engines of this type, ergo, would become exponentially more efficient and powerful with only marginal increases in size. I'm torn as to whether to scavenge such an engine with a twin screw or centrifugal supercharger. I suppose compound turbo-supercharging is always an option. As soon as I get the patent I will be posting more information. Its a really alien design unlike anything to have come before it.

 

[pmuller9]

It looks like the piston is being used to convert its own reciprocating motion to rotational motion.
That has been done by using piston side extensions riding in tracks in the cylinder walls.
In order to have a steep angle in the tracks to provide a lot of torque and decrease vertical track pressure, the tracks cycle twice providing two strokes per revolution.

If you have a shaft connected to the piston, it will have both rotating and reciprocating motion.
The reciprocating motion needs to be eliminated while keeping the rotating motion.

Any Similarity?

 

[DeltaV]

It looks like the piston is being used to convert its own reciprocating motion to rotational motion.
That has been done by using piston side extensions riding in tracks in the cylinder walls.
In order to have a steep angle in the tracks to provide a lot of torque and decrease vertical track pressure, the tracks cycle twice providing two strokes per revolution.

If you have a shaft connected to the piston, it will have both rotating and reciprocating motion.
The reciprocating motion needs to be eliminated while keeping the rotating motion.

Any Similarity?

Yes, very similar. But still different. I would like to see the research and prior work on the engine you are describing, as I've been unable to find anything similar to what I'm trying to do despite some cursory attempts to find such a thing.

 

[pmuller9]

I would like to see the research and prior work on the engine you are describing, as I've been unable to find anything similar to what I'm trying to do despite some cursory attempts to find such a thing.

I do not have anything to show from this project but I can do my best to describe it to you from memory.

Rather than having the shaft run through the pistons, it was decided to extend the piston pin outside of the cylinder through slots such that the piston would no longer rotate.
The extended pin would operate in tracks on the surface of a large diameter, parallel, external cylinder which is part of the power shaft.
This allowed multiple piston cylinders to operate around the common external cylinder and power shaft.

This particular engine configuration would have given way to the Dynacam Engine which is also known as the Revolver Cam Engine.

 

[Same Name For Everything]

From numerous stories I've read about Smokey, I'm feeling this is hitting the nail on the head. He was a genius, not only in racing, but also in taking advantage of situations in general.

Either way, for the sake of passing on information for anyone that is interested in this engine, this guy has at least 4 videos on his youtube channel:

Danny and the rest of us at SR have unearthed original DYNO pulls and further documentation that the engine ran as advertised. The only known such documentation. You can see more here: https://www.facebook.com/ThePhoenixEngine

 

[pmuller9]

Danny and the rest of us at SR have unearthed original DYNO pulls and further documentation that the engine ran as advertised. The only known such documentation. You can see more here: https://www.facebook.com/ThePhoenixEngine

Welcome to the Ford Six forum.
I want to thank you for posting.
This is what we want you to know in sincerity.

We don't doubt that the engine performed as advertised. That's not the problem.
On this forum we expect more detailed information on how the performance was accomplished.

There was important information that was missed while the engine was being taken apart.
For instance, it would have been an opportune time to set up a dial indicator and degree wheel to obtain the specs on the cam that was in that particular engine.
I noticed the engine had very deep piston dishes that would have brought the compression ratio down into the sixes, but no one addressed the engines compression ratio.
Was there any port work done to the head?
The video fast forwarded through the exhaust routing for stages 2 and 3 of the heat cycles.
Water routing and heat exchanger for the stage 1 heat cycle was never addressed.

On the "unearthed original DYNO pulls and further documentation" there is a lot of info that could be shared like, what is the intake manifold pressure and air temperature at peak horsepower, air fuel ratios, ignition timing ect...

This is why there is less than an enthusiastic response.
The lack of detailed information was a disappointment.

Maybe you could fill in some of the blanks?

 

[DeltaV]

Welcome to the Ford Six forum.
I want to thank you for posting.
This is what we want you to know in sincerity.

We don't doubt that the engine performed as advertised. That's not the problem.
On this forum we expect more detailed information on how the performance was accomplished.

There was important information that was missed while the engine was being taken apart.
For instance, it would have been an opportune time to set up a dial indicator and degree wheel to obtain the specs on the cam that was in that particular engine.
I noticed the engine had very deep piston dishes that would have brought the compression ratio down into the sixes, but no one addressed the engines compression ratio.
Was there any port work done to the head?
The video fast forwarded through the exhaust routing for stages 2 and 3 of the heat cycles.
Water routing and heat exchanger for the stage 1 heat cycle was never addressed.

On the "unearthed original DYNO pulls and further documentation" there is a lot of info that could be shared like, what is the intake manifold pressure and air temperature at peak horsepower, air fuel ratios, ignition timing ect...

This is why there is less than an enthusiastic response.
The lack of detailed information was a disappointment.

Maybe you could fill in some of the blanks?

Personally, before tearing apart an engine the Smokey himself put together, I would have liked a thorough inspection with borescopes to verify nothing is damaged, and then attempting dyno pulls with it BEFORE pulling it apart. Then pull it apart as you describe. This is an exceptionally historic engine and every detail must be documented, down to the torque requires to break loose every bolt, the original crankcase oil sent to blackstone labs for analysis, stereoscopic photomicrographs taken of the piston faces and all wear surfaces, X-ray scattering spectroscopy to determine alloy composition of all non-OEM parts, leakdown tests before disassembly and of the individual components after disassembly. The difference between science and playing around is whether or not the data is being recorded, and the quality of the science is correspondent to the quality of the thoroughness and methods of the data recording.

In other news, the block is being machined and the connecting rods are almost done. Yoke plates wont take long, and the cover plates will be equally simple. I still need to machine the crankshaft, pistons, cylinders, and make the intake manifold.

Also my company just purchased a screw machine and a van norman piston grinder so if you need bulk custom bolts or similar hardware or custom pistons let me know.

 

[wme013]

This is way over my head, I've read the discussion 2x times and understand about 20%.
This maybe useless info, but I remember my father talking about his adventures in Germany just post war. He found and was riding a DKW GP motorcycle. 2 cylinder twin with a 3rd cylinder acting as a pump supercharger.
Info...https://www.odd-bike.com/2014/02/dkw-supercharged-two-strokes-force-fed.html
Also another more recent odd supercharged engine is this Japanese YS supercharged model engines. 1 cylinder. The top of the piston functions as a normal thing. The bottom of the piston is the supercharger pumping a sealed crankcase via a timed rotary valve, pressure was stored in the intake tract. 2 pump cycles for 1 intake valve opening.
Have fun

 

[pmuller9]

This is way over my head, I've read the discussion 2x times and understand about 20%.

Do you have questions that we can answer to clear things up?

This thread is a discussion of ideas that evolved as time went on.

 

[wme013]

I get most of the mechanical stuff, it's the math and the source of the numbers.
When using a piston as a supercharger was brought up, I remembered my Dad's story. If you read the DKW thread you will that their engineers were creative, piston pumped twingle, rotary vane superchargers, there was even a twin crankshaft opposed 2 stroke twin with a rotary vane supercharger.
This was all back in the late 30's. Heck I even remember the Puch twingles at Sears.
I've thought about a flat twin 4 stroke using the YS idea of the bottom the piston is the supercharger, with a 180 deg crank the pistons compress together and 1 intake opens, a reed valve and a carb to the crankcase keeps there airflow in one direction.
Anyway it's an interesting read and keeps the gray matter aired up.

 

[pmuller9]

When using a piston as a supercharger was brought up, I remembered my Dad's story. If you read the DKW thread you will that their engineers were creative, piston pumped twingle, rotary vane superchargers, there was even a twin crankshaft opposed 2 stroke twin with a rotary vane supercharger.

I read the DKW thread and there was a lot of innovative engine designs that seemed to end after WW2.

If you look at the Bourke engine, the Scotch Yoke isolates the piston pumping from the crankcase and will allow any pumping compression ratio needed.
Also there is no need to add a lubricant into the intake charge.

I like the twin crankshaft, opposing piston design. See post #164 above.

If you use modern day direct cylinder injection you don't need to worry about over scavenging out the exhaust port.
You can blow as much fresh air into the cylinder as you want.

 

[wme013]

u use modern day direct cylinder injection you don't need to worry about over scavenging out the exhaust port.
You can blow as much fresh air into the cylinder as you want.

Sorta like a Detroit Diesel, anyway I'll keep reading

 

[DeltaV]

We just got official numbers from the third party testing for the original Bourke engine that I rebuilt.
2500-2600 RPM = 38% efficient
103 BHP @ 5000-6000 RPM = 52% efficient
Max Horsepower: 152 = 44% efficient, unknown RPM.
492cc, Naturally Aspirated, Carbureted.

Fuel was kerosene and Royal Purple 2 stroke oil with a ratio of 65:1.

Graphs and curves will be coming in the next two week or so.

If this third party isn't lying, then this is the worlds most fuel efficient gasoline engine as far as I'm aware. The original Bourke engine is oversquare and uses deflector pistons. There is much room for improvement even beyond this. Achates Power uses a twin crankshaft uniflow scavenged undersquare direct injected, turbocharged diesel engine, and achieves 55% efficiency. Achates Power also posses larger cylinders, so they get more volume to surface area ratio.

If we continue to improve and optimized the Bourke topology, we can beat Achates Power. Some of the things we could to to improve may include optimized scavenging, direct injection, using loop flow schnuerle porting rather than cross flow deflector head porting, moving to an undersquare bore/stroke ratio, increasing compression ratio, using gapless top rings rather than the archaic pinned rings it currently uses, among other things.

Who would have thought that a 1930's engine with two moving parts could beat 100 years of industry inertia and incremental advancement backed by every large corporation on Earth?

I am very happy with these numbers.

 

[pmuller9]

The numbers look good.

The efficiency versus rpm appears to verify what we talked about previously concerning the Dynamic Compression Ratio and Volumetric Efficiency.
Because of the piston ported inlet below the piston, the DCR and VE is low at low rpm and increases as rpm increases.
I suspect below 2000 rpm the DCR and VE is low enough so that detonation is not guaranteed.
We had discussed ways to improve the DCR/VE at low rpm including reed valves.
I prefer the rotating slotted tube induction so the inlet timing can be varied with RPM to maintain a more constant engine VE over a very wide rpm range.

I will be interested in seeing the graphs and curves when you get them.
I'm hoping the data includes exhaust temps.

 

[wme013]

In the beginning...https://www.mecum.com/lots/SC0522-502934/1972-chevrolet-vega/

 

[Same Name For Everything]

Welcome to the Ford Six forum.
I want to thank you for posting.
This is what we want you to know in sincerity.

We don't doubt that the engine performed as advertised. That's not the problem.
On this forum we expect more detailed information on how the performance was accomplished.

There was important information that was missed while the engine was being taken apart.
For instance, it would have been an opportune time to set up a dial indicator and degree wheel to obtain the specs on the cam that was in that particular engine.
I noticed the engine had very deep piston dishes that would have brought the compression ratio down into the sixes, but no one addressed the engines compression ratio.
Was there any port work done to the head?
The video fast forwarded through the exhaust routing for stages 2 and 3 of the heat cycles.
Water routing and heat exchanger for the stage 1 heat cycle was never addressed.

On the "unearthed original DYNO pulls and further documentation" there is a lot of info that could be shared like, what is the intake manifold pressure and air temperature at peak horsepower, air fuel ratios, ignition timing ect...

This is why there is less than an enthusiastic response.
The lack of detailed information was a disappointment.

Maybe you could fill in some of the blanks?

Thanks for the welcome. Sorry for the delayed response. After I posted we got caught up in an eBay event: The post was meant as an introduction to the project. There are a series of videos on Danny's page and the link to the FB page has periodic updates as well. As the project name Phoenix implies, we are seeking to resurrect the technology and modernize it. We will continue to post updates to the FB page and additional videos will be shot. The engine and vehicle that are the most important are the numbers matching Horizon and the original HVC that was in Smokey's daily driver. Meticulous measurements and records will be kept. Of the three dyno pulls from SwRI we posted the middle one on the SunRock FB page in May of 21. As far as the overall function and heat stage routing, it follows the Patent pretty closely. A couple of the videos that Danny did have him giving a tour of the engines and their function: 1, 2, 3