Another Henry Smokey Yunick Hot Vapor Engine Thread 7

[SameName4Everything]

First, I am not an automotive engineer and I didn't spend the night at Holiday Inn. I jumped into this project only a few months ago and had a leg up because I know Danny Soliz very well and he is a life long adherent of Smokey, has studied the HVE and actually has 5 of the 10 known HVEs including the numbers matching Horizon and its engine. Overview:

https://www.youtube.com/watch?v=uNLpHGy3fVw

Running on a stand:

https://www.youtube.com/watch?v=vDL65UUjOss&t=431s

Discussing cams for the Iron Duke version:

https://www.youtube.com/watch?v=NS9serKZ30s&t=263s

After having read what was readily available I have gone further down the research trail than most. I was aided by documents from DeLorean's files and other documents and articles from the past. What I have gleaned is that it is a polarizing issue driven by Smokey's legend, myth or infamous reputation. The claims are well know, but there is no proof. My question is this: Would the data pulled from 12 Dyno pulls and 10 road tests of MPG from SwRI be proof? How about reports by engineers at SwRI? Or reports and quotes from someone like Gregory Flynn who ran GM's Motor Division attesting to it working? If those showed approximately the 50MPG, Zero Emissions, 1.8 HP/CI from a 1.3l Engine using a carburetor and other tech available in 1982, would that be enough for people to say it worked?

 

[BrianPetersen]

Old thread on same topic:

https://www.eng-tips.com/viewthread.cfm?qid=176663

 

[BrianPetersen]

Elsewhere ...

https://www.yellowbullet.com/threads/smokey-yunicks-hot-vapor-engine-why-isnt-it-used-today.2552975/

Pay attention to posts 18, 22, 26 ...

Smokey Yunick was the master of keeping his mouth shut. He'd keep some critical aspect of whatever he was doing secret, but without knowing that trick, you would never get it to work. What those secrets were ... in many cases we'll never know.

I suspect that these engines, with sufficient trickery applied, may have been able to pass 1980s-era emission standards without a catalyst and with carburetors, but there is no way they would pass today's emission standards.

With very high-temperature operation, NOx is a concern. With lean operation, lean-misfire is a concern. With high-temperature intake charge and forced induction, detonation is a concern.

Modern direct-injection, variable valve timing, etc address at least some of the issues Smokey was trying to address otherwise, before that technology was production-ready.

Bear in mind that Otto-cycle engines that operate on natural gas, aren't appreciably more efficient or powerful than comparable engines that operate on liquid fuel, nor do they miraculously make NOx emissions magically go away.

 

[SameName4Everything]

My point is, that from what is available to the public, who knows what is sitting on the shelves at the OEMs, there has been no "proof" of MPG, no "proof" of CO or NOX compliance, no proof of HP. It was all alluded to in magazines or Smokey interviews but no body ever had hard data or 3rd party verification of the claims. Would dyno pulls and contemporaneous reports from engineers like Flynn and Karl Springer lay the speculation to rest. Especially if Smokey was not present for the test and the cars were simple dropped of in San Antonio for days at a time? And, I have read the old post on this thread an a score of others. Not one ever shown or claimed to know what pulls showed or 3rd party verification. Obviously, Daniel Soliz ran one on a stand, the Fiero is shown on the Dyno and the Horizon is shown being driven in the Swedish video, but that just proves that it works, not that it works as has been claimed. So I will ask again, If hard data was available and it showed results, would that be enough? Or does an new prototype need to be built.

 

[Lou Scannon]

It would help a lot if there was a scientific theory to explain the physics and chemistry behind any such claims. Anyone can espouse a bullshit explanation for this or that and fake test results, but actual scientific theories are harder to produce and easier to debunk if flawed.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[3DDave]

I would trust Smokey the way I would trust Penn or Teller in a card game. All of them are/were honest. What's not clear is what they are/were honest about.

 

[SameName4Everything]

So, @Lou Scannon, What you are saying is , that in my hypothetical: The head of emissions of SwRI and the former head of GM Motor Division offered up bullshit explanations and faked test results? @3DDave same question. If as I stated in the hypothetical, the car(s) were at SwRI for days at a time and Smokey was not present. Then test were conducted. SwRI and a SAE Board of Directors member were part of Smokey's magic and the results from dyno runs and MPG test were fabricated? I am just asking, what entity or persons could provide proof for engineers/scientists that the HVE worked as advertised back in 1982?

 

[GregLocock]

SWRI has a hmm, mixed reputation.

Cheers

Greg Locock


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[Lou Scannon]

So, what's the scientific theory?

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[SameName4Everything]

https://uspto.report/patent/grant/4592329

 

[GregLocock]

" reports and quotes from someone like Gregory Flynn who ran GM's Motor Division attesting to it working? If those showed approximately the 50MPG, Zero Emissions, 1.8 HP/CI from a 1.3l Engine using a carburetor and other tech available in 1982, " and GM didn't take it any further because they were successfully fending off competition from the Japanese? Pull the other one, it's got bells on.

Cheers

Greg Locock


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[BrianPetersen]

Just because you have a patent, doesn't mean it actually works. (I'm not saying Smokey's engine "didn't work" ... just saying, take what it says in a patent, with a grain of salt.)

Just because you have a patent, doesn't mean that patent contains ALL the information that you need in order to make the concept illustrated in the patent, work. (They never do.) Smokey was very good at keeping his mouth shut.

Now, let's scrutinise Smokey's patent linked to above, and compare it to "modern state of the art" - some of which involves engine features that hadn't been developed at that time.

"Background art."

The bit about fuel not getting completely vaporized, first I will point out that modern fuel injection is better at distributing that fuel, and secondly I will point out that engines that run on propane or natural gas don't have miraculously high efficiency compared to those running (properly) on liquid fuel.

The bit about "carburetor double-pull" is a non-issue with port fuel injection, or direct-injection.

The patent is silent about how to control detonation, other than "hand-waving" and saying "it doesn't detonate".

The patent is silent about how to get a normal spark plug to fire the supposedly lean air/fuel ratio, although the patent doesn't really get into that.

So, what do I really think is going on (at least to some extent)?

Smokey was a smart guy. He built lots of high-powered racing engines. He knew a thing or two about compression, and charge turbulence, and the like. I think there was some port-shaping trickery, and some squish-clearance trickery, and perhaps some clever combustion-chamber shaping, to achieve really fast-burn combustion. (Modern engines do this, too.) The advantage of his full-vaporisation strategy is that he didn't have to worry about charge turbulence "centrifuging" liquid fuel out of suspension. It's pretty likely that the spark plugs and/or ignition system contained a few secrets, too.

And the other thing I suspect ... is cam timing trickery. Everyone has heard of the Atkinson cycle, or its forced-induction counterpart, the Miller cycle. Smokey's engine could have been an early implementation of the Miller cycle. Whether he did it by really early or really late intake valve closure, who knows ... I suspect the latter, as it's more compatible with valvetrain designs that were common at the time. Use late intake valve closure to cause the effective expansion ratio to be greater than the effective compression ratio ... use the turbo to compensate for the loss of volumetric efficiency when the driver asks for full load ... machine (otherwise) crazy compression into the pistons and head with really tight squish clearance to get good charge turbulence and a fast burn.

The modern V6 gasoline engine in my driveway achieves the Atkinson cycle upon command by fiddling with the intake and exhaust camshaft timing - the engine has variable valve timing with independent control of the intake and exhaust sides. That didn't exist (in production) in Smokey's era.

I would love to see an independent lab test out Smokey's engines to see what's really going on ... and perhaps a non-destructive look into the combustion chamber with a tiny camera through the spark plug hole to see what he's done with the pistons and the combustion chambers.

 

[BrianPetersen]

One other thing. If my suspicion is correct, it's rather likely that modern instrumentation and testing would find Smokey's engine to have high NOx emissions. Slightly lean of stoichiometric + high compression + fast burn = NOx.

 

[SameName4Everything]

@BrianPeterson: "One other thing. If my suspicion is correct, it's rather likely that modern instrumentation and testing would find Smokey's engine to have high NOx emissions. Slightly lean of stoichiometric + high compression + fast burn = NOx"

From the DMC memo from Buck Penrose to Bill Kennedy (Jan 11 1982) regarding the Jan 1982 SwRI emissions runs where the DeLorean engine passed NOx was 1.0. It goes on to further state that the prospects for meeting California standard of .7 for 1982 were excellent. From the same memo: HC .40 CO 2.2

 

[BrianPetersen]

From

https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P100O9ZP.pdf

That NOx limit "1.0" sounds like the EPA limit which applied from 1981 (the era in which these engines came from) - the first line in that table. A number of production vehicles squeaked through those standards with no catalyst early on. Carburetors survived in some production cars until 1989 or thereabouts.

Tier 3 limits apply now:

https://www.epa.gov/greenvehicles/light-duty-vehicle-emissions#standards

There is now not a limit on NOx alone, or HC (now called "non-methane organic gases" NMOG) alone, but rather a total of the two, and the fleet average of the total of those two is 0.03 grams per mile. Just a wee bit tighter than what applied in 1981. Just a little.

This is not to take away from Smokey's work ... it's just that many of the things that he did, have now been addressed in other ways, and it's pretty unlikely that the no-exhaust-aftertreatment approach could have persisted.

The production spark-ignition gasoline engine in the Toyota Prius today is supposedly a smidge over 40% brake thermal efficiency at its best operating point, others are not far off, and that particular vehicle is designed to keep the engine operating as close as it can to its best-efficiency conditions as much of the time as it can.

 

[SameName4Everything]

Just because you have a patent, doesn't mean it actually works. (I'm not saying Smokey's engine "didn't work" ... just saying, take what it says in a patent, with a grain of salt.)

Just because you have a patent, doesn't mean that patent contains ALL the information that you need in order to make the concept illustrated in the patent, work. (They never do.) Smokey was very good at keeping his mouth shut. A couple of pertinent quotes: , “Still, Smokey took much of the knowledge with him to the grave. As Smokey's daughter Trish Yunick puts it, "A patent application is a balance between disclosure versus secrets. You want to reveal just enough information to get the patent, but not so much that people can reverse-engineer your ideas. Smokey is gone, and some of the secrets went with him." Hot Rod Magazine. “It is really quite simple, and I am careful not saying too much. This is the only way I can be sure nobody knows how the system exactly works says Smokey” Swedish Hotrod Magazine

Now, let's scrutinise Smokey's patent linked to above, and compare it to "modern state of the art" - some of which involves engine features that hadn't been developed at that time.

"Background art."

The bit about fuel not getting completely vaporized, first I will point out that modern fuel injection is better at distributing that fuel, and secondly I will point out that engines that run on propane or natural gas don't have miraculously high efficiency compared to those running (properly) on liquid fuel. The patent was of his Phase I engines, He had plans for additional gains.

The bit about "carburetor double-pull" is a non-issue with port fuel injection, or direct-injection. The introduction of EFI was contemplated by Yunick and Knudson as early as 1980.

The patent is silent about how to control detonation, other than "hand-waving" and saying "it doesn't detonate". Flynn, Springer and Ingalls confirm

The patent is silent about how to get a normal spark plug to fire the supposedly lean air/fuel ratio, although the patent doesn't really get into that.

So, what do I really think is going on (at least to some extent)?

Smokey was a smart guy. He built lots of high-powered racing engines. He knew a thing or two about compression, and charge turbulence, and the like. I think there was some port-shaping trickery, and some squish-clearance trickery, and perhaps some clever combustion-chamber shaping, to achieve really fast-burn combustion. (Modern engines do this, too.) The advantage of his full-vaporisation strategy is that he didn't have to worry about charge turbulence "centrifuging" liquid fuel out of suspension. It's pretty likely that the spark plugs and/or ignition system contained a few secrets, too. Soliz is now doing forensics on the engines that he has. He has some insights to some of what you address but to get back to the issue, I am more concerned about the 81/82 runs at SwRI and those engines: AFAIK regular spark plugs and distributer.

And the other thing I suspect ... is cam timing trickery. Everyone has heard of the Atkinson cycle, or its forced-induction counterpart, the Miller cycle. Smokey's engine could have been an early implementation of the Miller cycle. Whether he did it by really early or really late intake valve closure, who knows ... I suspect the latter, as it's more compatible with valvetrain designs that were common at the time. Use late intake valve closure to cause the effective expansion ratio to be greater than the effective compression ratio ... use the turbo to compensate for the loss of volumetric efficiency when the driver asks for full load ... machine (otherwise) crazy compression into the pistons and head with really tight squish clearance to get good charge turbulence and a fast burn.

The modern V6 gasoline engine in my driveway achieves the Atkinson cycle upon command by fiddling with the intake and exhaust camshaft timing - the engine has variable valve timing with independent control of the intake and exhaust sides. That didn't exist (in production) in Smokey's era.

I would love to see an independent lab test out Smokey's engines to see what's really going on ... and perhaps a non-destructive look into the combustion chamber with a tiny camera through the spark plug hole to see what he's done with the pistons and the combustion chambers. Going down that road myself. That is why I am curious to know if a series of dyno pulls and reports by engineers of the caliber of Flynn and Springer would be enough to put the matter to rest. Soliz did a live YT where he opened up the Iron Duke that was most likely part of the abandoned partnership with Crane to make a kit version. I am not sure if it is archived, but there is a video about some of the cams that may have been used.

 

[RodRico]

Smokey's patent discussing heating the fuel air charge sounds like a modest form of supercritical fuel injection.

P.S. Though transonic is out of business, the topic of supercritical fuel injection remains active
see

https://www.technologyreview.com/2009/08/11/211065/supercritical-fuel-injection/

for example

 

[SameName4Everything]

@BrianPeterson: Some insight into the thinking after the Jan 82 test from the summary report:

"With the current fuel and emission control systems installed on the
engine, it probably could not be made to pass the 1983 California standards.
If a three-way catalyst with feedback fuel control could be successfully
fitted to the engine, it should be possible to meet the 1983 California
emission standards."

 

[GregLocock]

In other words, the vaunted low emissions were not low enough to get rid of the cats, so there was no significant practical advantage there.

"50MPG, Zero Emissions, 1.8 HP/CI from a 1.3l Engine "

I was driving an 80 mpg car in 1984. Or at least that's what the press announced. It was actually 80 mpg at 30 mph on a flat road. It used a small 3 cylinder from Japan as the base of the engine. Its grandson became the Rover K series engine.

So 80 hp/litre. Certainly practical at the time, Lotus' 907 was 80 hp/litre (claimed, ahem) in 1976. Redline gets you there.



Cheers

Greg Locock


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[Lou Scannon]

Smokey's patent discussing heating the fuel air charge sounds like...

Heating the fuel air charge is a good idea, IF it occurs after TDC compression. Other than that, (liquid fuels only) you only want to add enough heat to make sure the fuel is adequately vaporized and sufficiently evenly mixed to enable more or less complete combustion of the available reactants. Additional heat before TDC compression beyond that amount will show up as reduced volumetric efficiency and/or reduced effective expansion ratio and hence reduced output, other factors being equal.
Now if there are other factors being manipulated to offset the VE/EER reduction, don't send me a link to a patent or startup website, elucidate the concept yourself if you understand it, otherwise, study up then come back and elucidate.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz