The NEED and Effects of Expansion Gases within an IC Engine Cylinder

Hi All
A new “good” gases topic to chew on.
Since the DOW is dedicated to “Drive On Wood” and “Power On Wood” then woodgasification is all about making useable shaft power with the woodgas.
From a today practical stand point then you are going to be making this shaft power with one of the today far over existing in-place 10,000,000,000 (10 BILLION +) piston internal combustion engines already on the face of the planet.
NO need for a new woo-woo engine at all.

Expansion gases to push that piston down to make shaft power are not just the commonly accepted combustible gases.
Expansion gases are the uncombusted and un-readably combustable/oxidizable gases of nitrogen primarily; carbon dioxide second; then trace argon, and such. H2O “water” plays parts in-cylinder too.

These “good Witches” gases get a bad rap in the gasification part of it. Well . . . screw that noise says engine guy ME!
In the actual IC piston engine these good Witches gasses get heated. They expand greatly. Pushing onto the face of the engine pistons greatly. (A Stirling cycle engine relies Exclusively on these - piston steam too)
If you have a gases empty cylinder and heat it - NO PRESSURE RISE OCCURES!
A moveable piston on one end of that cylinder will not be usefully moved at all!
You will just be heating the cylinder walls and piston materials for no shaft power making benefits.

So not interested in making complex chemicals but in realistic making shafts go around for a purpose to make useable power . . . Time To Stop Hating Nitrogen and Carbon Dioxide but praise them for combustion heat absorbing and expansion pressure pushing on those pistons!!

Much more on this if there is an interest.

Steve Unruh “the engine guy”

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I write now for these guys ands gals. Invite other to join these power making Practicalists.

Learn to love your IC in-engine Nitrogen.
I just seached up and read 20 info links to NitrousOxide NOS engine power boosting. You see it in movies. See it at auto parts stores, in HotRod/Performance magazines. It’s now the IN-THING to do. Sells more product. More magazines. More advertising space.
Not one Net article got the nitrogen in-cylinder power making part of it addressed correctly.
N2O stuffed into the cylinder aye-yeah does stuff in more oxegen alright. But . . . after you stripped that oxegen away you are also left with in-cylinder stuffed in more than a normal amount of nitrogen gas too.
So, yeah dump/inject in more hydrocarbon fuels molucules to make more oxidzing HEAT with this extra in-cylinder oxygen stuffing.
Again - until you are heat expanding some kind of gasses you will not be applying more pressure/duration against the moveable piston face. Your NOS injection DID Add more expansion gas nitrogen in-cylinder TOO!
Supercharging and turbocharging adds more in-cylinder atmopheric nitrogen expansion gas also.
I have books and books on that. None ever give added stuffed in nitrogen any credit either. Bitch and complain about it. Only focus on stuffed in oxygen.
Strictly horsepower making with no other considerations is myopic.
Sumo westling, power wieght lifting. Ever see one of those fellows have to unload a full van trailer of 40,000 pounds tare weight? Pitiful. Now muscle joke do that all day for a full 8 hour shift. You want lean, mean, wiry and long gut-it out toughness. Arm wrestlers.

So a gasifer passed through added nitrogen IS A PISTON IC ENGINE BENIFIT.

Next in-cylinder carbon dioxide.

Steve Unruh

I still say NO to the dreaded nitrogen!
If we were able to take it out of our gasifiers we would be getting a more “supercharged” gas. Now, we wouldn’t be getting something for nothing. Lbs per mile would be the same except for when our foot is in it, using the higher hp.
Any gas of course is going to expand. I would rather that gas be CO converting to CO2.
Also water vapor to steam is an added benefit, using some of that heat energy!


You betcha’ on the IC Engine in-cylinder CO2 expansion gas as a woodgasifer delivered benefit TerryG.
BEST that the gasifier made CO2 carbon dioxide to CO carbon monoxide be “reduction” maximized.
Takes in gasifer surplus Heat energy; lengthened out residence times to maximize for this.
Carbon dioxide out of the gasifier can ONLY be only an IC engine expansion gas. Still needs in-cylinder made heat for the expansion/pressure rise of this in-cylinder carbon dioxide.
Carbon monoxide out of the gasifer to the IC engine cylinder WILL make both this needed Heat energy and carbon dioxide expansion gas!.
Same. Same. In an IC piston engine carbon dioxide IS GOOD.

Nitrogen reduction out of the gasifier, practically, always comes back to the same:
Use an actual wood fuel in.
This will have a mole weight of at least 20% +/- of actual oxygen molecules in it. Use THESE maximized for your needed in gasifier oxidization. This allows absolutely minimizing gasifier system atmosphere air let-in to under 3% equivalencies. Less atmospheric nitrogen in then - less passed trough nitrogen out.
Gasifier gases mixes out then nitrogen down from 60% range to a low 40% range. A more energy dense fuelgas mix.
Only heavily outside energy supported Lab works, and big stationary Industrial can do better with refined/densifed pure oxygens inputs.
Since we individuals as practicalist cannot eliminate all into engine nitrogen then why spin-out hating it?
Make peace. Appreciate. And use what you have to live with. As much as an expansion gas nitrogen is a combustion modifier for engines materials life benefits.

Practical, real, today world use of piston internal combustion engines often requires the use of exhaust gases recirculation for transient in-cylinder heat/pressure spiking moderation. They worked that out in-Labs back in the late 1970’s.
They trialed with argon gas and other bottles welding gases. For real world in-engine use a bright boy figured out that the IC piston engine was producing it’s own invert gas in exhaust carbon dioxide. So . . . cooled, filtered, and meter that back in for transitional needed benefits.
SO . . . how can carbon dioxide be the Ba-a-a-ad Gas we are now popular Cuture spun with?? Critical Plants food. Makes more fuel woods.

Steve Unruh

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“how can carbon dioxide be the Ba-a-a-ad Gas we are now popular Cuture spun with??”

Moderation of course. Everything needs it’s balance!

(I thought you would touch more on the water heat extraction)

Remember, we have LESS nitrogen with woodgas, not more. What we’re really low on is oxygen, about half as much as gasoline. I made my comments on this topic here:

0.0383 of a % is carbon dioxide in our atmosphere… How much less would be moderation? What most people don’t realize is that is we halved the CO2 in the atmosphere we would loose all plant life on earth. The ocean moderates CO2 (or at least that is my understanding). If people were really worried maybe they would focus on cleaning up the ocean to make it more efficient at the moderating. Just my 2 cents.

I’m with Steve on the CO2 is plant food… It’s not a bad gas…

TerryG, really, thanks for responding.
No responces and I’d would have just let this die here, and do this talking person to person phone and e-mail.
What I’d noticed was specially 4-6 newer members here now reading who “bio” show actual made up working vehicle gasifier systems. Two fellows in Idaho; one in Oregon: one in Illinois; one in North Carolina and one in Florida. Pictured systems show them as like you and I not WK system builders/users.
So why bury this “I’m OK, You’re OK” back on the Premuim side, eh?

Actually probably closer to 200+ DOW members like you or me can walk out and make woodgas shaft power in our IC piston engines. Just sweat/cut the wood fuel. I only anymore care about those willing to limit their personal “CO2 Footprint” with their own woodsweat for giving out the good stuff info helping.
This fits the DOW. Admittedly fits few, if none of the other Net all-biomass venues. Why they do so real actual useable little in my opinion.
I write for these fellows woodfuel Doing, you and me. Woodgas making actual IC engine users.

H2O into IC piston engine benefits was re-wrung out again a lot in the 1970’s.
Just like NOS this was all originally done by the WWWII combatants in high performance aircraft. Same with turbo’s and supercharging. These also 1930’s high end Formula raced trialed. Up to 40 PSI boosts!! (“new” introduced 1 liter engine restrictions)
“Water” spraying into the IC piston engine was primarily a benifit to control thermal out of control spiking conditions. This was because of the droplet vaporizing heat absorbing. Specific cylinder heads, valves and piston top engineering got rid of many of these “problems” benfiting from water misting/injecting. Post 1940’s HC advanced fuels improvements got rid of more. I970’s “emmisions” hung-on 'fixes" had engines overheating re-introduce these problems. Manufacturers dropped thrier most problem prone engines. Refined others then to take emissions systems heats. Late 80’s electronic controlled ignitions and port/runners point fuel injections reeled back in the last source problems for any water injection benefits. Now direct injection systems have stepped this up another level yet.
Putting actual H2O as pre-vaporized just like “the nitrogen complaint” will in-cylinder volume displace out oxegen and hydrogen and carbon heat making oxidizing fuels molecules.
For H2O to have the in-cylinder expansion benefits of nitrogen, argon, helium or even hydrogen it’s high specific heat works then against it.
This is in steam engineering books and charts. H2O is Great for heat energy absorbing, storing and even transfering. Steam heating. Take TOO much heat out of in-cylinder IC engines though for it’s expansion ratio for a net reduction of piston power pushing for the heat it wants. Blow it out hot - wasted energy. Energy wring it out with engine design it in cylinder condenses. Lubricant washes - wear accelerates. Oil contaminates - wear accelerates. Nasty, real, in IC piston engine effects. Why the 1970’s “water into power” efforts got left in the history dust-bin that were outside of massive steam turbines.
You certainly do not the the in-cylinder IC engines conditions to have the heat and pressure to disassociate the H20. Look it up. You do not have the Mass Hot glowing reactive woodchar in engine cylinders for the activated carbons to do a water to gas shifting. All in-cylinder carbons are far better direct oxidized used to make more in-cylinder heat and CO2.
So the advanced Euro way of over-chilling the gasifier out-stream to de-humidfy; then reheating for a very low apparent humidity to IC engine delivered fuel gas mix really probable is IC piston engine the Best for power and efficiency.

In-gasifier affects of H2O are completly different, covered much on the DOW in other topics. This topic is about the in-engine limited scope.

Secondary air-in humidity to the engine along with gasifier H2O out are again wide ranges of variables we just have to accept and learn to love for in-engines effects.
Hating, will not make them disappear either.
Use them for engine benefits. A challenge then.

Steve Unruh

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(had to ask what many are thinking)
Well 50 years of really, really live active following “the progress” of IC piston engine replacements. Been easy enough to go back 15 years before that with in print promotion and documentation.
Stirling, minigas turbines, microsteam, Wankel , ect, ect, ect. Where are they in actual deployment now?
Past all of the conspiracy theories of being shelved and sunk is thermal efficnecy realities.

These first two WERE engine power reliant on regenerative cycles of heat expansion gases and even the heats themselves.
All shaft power making heat engines rely on maximizing the difference between a cold side and a hot side. Simply put the hotter the hot and the colder the cold and more time you can cycle between these the greater your fuel/heat to shaft conversion effency.
70 years of multi modern intense effort of engineering and Stirlings peak stuck at 29% heat value of fuel put in to shaft power out. That’s for a very high tech exotics materials $100,000 engine. My $200 and $500 Honda IC piston engine lawn mower can do this handily.
Same story for the microgas turbines.
Why? These two must maintain constant heat materials exposures to 3X and 4X the levels as the Honda IC pistons engines. For them either APPLIED heat makes pressure force, or flow reactive force.
The Honda’s you have a suck in cooling charge cycle. Bit of heating up compressing cycle. Then a heat burst resulting in a pressure rising/falling short duration cycle. Followed by a let the un-converted to shaft power remaining heat and pressure out cycle. Repeat. Repeat. Repeat.
Air rifle cross check this. Pump-up and stored pressure types. Make lots of gas compression heats. This is all bled off and lost before application. NONE gets used in the power release. Cycle rapidly and the receiver will actually released gases cool reducing seen pressure, therefore velocity power.
Barrel cocker spring-air. Has an open ended to atmophere (nitrogen) piston. Your muscles heat a bit cocking/setting. Spring heats a bit too. These lost. Minor. Releasing the cocked piston slam compresses the air heating it for even MORE of an energy power release. Cock and release rapidly and the receiver WILL heat. That heat gets to the cocked cylinder “gases” transfered. Your delivery power goes up. Your velocity rises. Really see this cycle heating on cartridge repeaters. Those YOU must slow cycle rates to cool or external cool OR materials damage, and “cook-offs” Will occur.

Micro steam with two hundred of years developement stuck at 16% heat value of fuel in to shaft power out conversion. THATS with triple reuse steam expansion. Last very serious efforts to improve on this by a brothers pair had them running cylinder temperatures so high the the metals cylinder were hot translucent and the moving piston could be photographed inside. Same materials destructive temperatures then. Valving sealing then became the stopping point. So again the drive up into exotics and costs. Easily costs powered instead with IC piston engines. And No small steamer ever really had usable water recovery recycling. Use much more water than fuel.
Back to when your piston face pushing is a let-in externally made pressure release there is too much of the pressure making/delivery “system” subject to too high of constant temperatures and pressures. Sure way to drive up your costs, overall complexity and have higher non-deliverable energy losses.

This should drive home point out that even though in an internal combustion piston engine cylinder that the combustion temperature may spike at 2200-2500F this is the center of the combustion globe. Edge temperatures do not run that high. And this temperature spike is made inside/out and of a short duration. WITH it inside/out made much easier to get materials forgiving rational HEAT to shaft power converting. Old way was cast iron pistons. New way ecludic coated pistons.

Now Wankels. You can read much about compression ratios limitations. Well THAT does hammer internal combustion possible efficients hard. Even piston crankcase pressurized 2-stokes have this limitation.
Here is another Wankel set back. Manufacturing costs.
Take a nail or pin. A piece of string. A pencil. EASY to make perfect circles. Shortened the string. Easy to make perfect concentric circles. Now make me perfect paralle lines. Then make a pair of these for a perfect square. Now YOU try making a Wankle internal shape.
Same thing in metals.
Another design limitation. Rotor edge and tips sealing. Lobe tips can really only have a single gasses areas pressure seal to be able to follow the wankle curves.
My 13,000 RPM round piston Stihl engines use two pressure sealing piston rings. The B&S, Kohlers and the gasoline vehicles use three piston sealing rings. My much higher compression diesels use four piston pressures sealing rings. Ha! Now you know why you never will see a compression ignition diesel Wankel.

So . . . in this past 70 years IC piston engines have just refined better and better. Mazda themselves with a manufactured and deployed Miller cycle engines. Complex. But less expensive with better durability than a Wankel.
Honda and Toyota with emulated Atkins cycles deployed driving around worldwide. Honda with a few hundred thousand deployed true Atkins cycle piston engines out now too.

There are many worldwide serious engine suppliers out there that IF they could truely refine out a better way heat engine, they would. They want to put their competitors out of business.
You bet they use in-cylinder expansion gases to the best effects.

Hyundai big ship piston engines at 178 to 300 rpm are said to be putting more motive shaft horsepower for the highest fuels use efficiency conversions on the face of the planet.
They use atmospheric air with the 78% nitrogen.
And lots of it for the extremely heavy wastes oils that has to be steam heated just to be able to “fuel” inject it.

Steve Unruh

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Steve, that dissertation above reminded me of this guy who invented a six stroke IC engine. I wonder if that ever went anywhere.

Hey DonM I don’t figure you and I will live long enough to see the end results of this one, other added power cycles systems, and newer idea heat engines like that Cyclone engine.

I’ve read this article before. Good balance to it of pro’s and cons. Distilled water supply costs as one of the real deal breaker cons.
My heat energy recovery pencil isn’t sharp enough to come up with their 40% fuel use reduction though. I make it as only maybe 15% realistic.
Another concept engine added the heat use 2nd power cycle as cooled/condensed filtered engine exhaust put back in for just another heating expansion go-around cycle. Made more “Material World” (Madonna?) sense to me. No in cylinder water wear and contamination issues then. Steam cylinder lubricant is far different from IC engine lubricants!

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i trow in a few of my cents…
A gas-less cylinder ( as such is nearly impossible since absolute vacuum does not exist ) but for the dialog sake…
if heated this cylinder = applying energy, ergo an change of state will take place. resulting in either a greater vacuum, since the cylinder gets bigger, or a decreasing of the vacuum if the cylinder gets smaller.
anyhow, applying energy leads to change of state and will be measurable/noticeable
If any moveable piston is installed, it will change position. period.

Using a IC engine, modified to resist H2, will not produce Co2, only 9 times its weight will be water, it needs 8 times its weight of oxygen or 34 times its weight in air.
of course, combusted with oxygen, without nitrogen, any combustible will perform better then with air.

The soul problem to counter would be the heat development and according the pressure build ups when igniting the mixtures
( data on the fuel flame charts )

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Altering the gas contents of the gasifier is preferable to reduce the amount of C02 in the gas going to the IC engine.
As the name says 1 CO has 1 chaperone for the dancing accordingly so much Nitrogen as chaperone ( diluting )
1 Co2 has 2 chaperones and as such also double the amount of Nitrogen
The most gain in power-efficience is to tweak the Co2 output of your gasifier.
Less Co2 = far less Nitrogen in your gas…

Second to gain is your intake efficiency, any obstruction should be avoided ( polishing, enlarging intake valve, cam opening time… )
Blower / compressor, Turbo… it all works
Also for stationary, a tank with premixed - pressurized gas, forcing the gas trough the intake into the cylinders…

Third: oxygen concentration to mix with
A promissing technology is using an Nitrogen separation membrane
The power gained is dramaticaly more then the power cost…

We should not stop with “thinking outside the box” but accelerate in discovering the new technology’s
Don’t start with stumbeling over problems, find solutions…

we don’t need to modify our engines… we need to modify our perceptions…

Don’t forget… Co2 is a world wide problem, but not with gasification…

For example a test we did perform here already…
1Kg Carbon + 1 Kg Co2 + 1Kg oxygen gave almost pure Co (93,4%)

Building pressure in a piston by decreasing the volume will generate heat.
Using a piston in other way and making it run with expanding compressed air, will make it cool.

The heat in an IC engine comes from the exploding, deflagrating or detonating from a combustible mixture…
Reduce the amount of energy in this mixture = less power and less heat

Steam pistons… the first problems for the early developpers: expanding steam created to much water condensate in the cylinders, so they used higher temperatures to counter that ( steam in - steam out ) and less efficient was the energy - to power balance…

Energy to real life power
Its a balance act, nothing difficult, only needs the feeling of the power you’r working with…
with the experience you learn to find you’r gasifiers balance point…
But… putting weight on one side needs the knowledge to put the correct counterweight on the other side…

Steve, Koen,

I don’t know the temperature of compression temperatures. Knowing that engines run cooler on WG and the vapor pressure of water is a lot lower than gasoline, I thought maybe the water vapor(fog) could flash upon ignition, adding to the push.
If we could employ a phase change we would have significant gains!


Hi Guys; I have been trying to read and get something out of this thread, but so far little has been gleaned. Is what you are discussing really relevant to us back yard do it yourselfers or are you talking theoretical. I hate to miss something if it is pertinent, but I’m not the thinker type. I know one time Steve you told Mike L to read the first paragraph and then skip to the last paragraph ( I tried that with no success). IF this is pertinent to us hackers would you please do what you use to ask so often when you didn’t have a fast internet----- could you please post individual pictures because the computer in my head will not grasp the videos you are posting.
This is NOT a sarcastic post. I really try to learn from all of your information and posting, but this one is getting away from me.TomC

Hi Tom, I’ts mostly theory. With enough thoughts running around our heads, once in a while something might pop up to make a difference.

Keep going . . . if for no other reason than adding to the already rich deposits in the DOW archives.

My purpose of this topic to any wood to shaft making energy hacker is very simple:
Just stop listening to “nitrogen”, “carbon dioxide” fear talking in gasifer outgas streams when your intended gas supply is going to be used in a very flexible, forgiving Internal Combustion Piston Engine!!

I am a 5000+ hour working internal combustion engine “combustion performance” technician experienced on hundreds of different engine types in various states of conditions, and say this with authority.

Just make your producer gas.
Accept as always a changing flux in it’s range of variable combustable gases.
Just Run Your engine, with Your made gases blends, for YOUR purposes anyway. Ignore all else.
Then let YOUR engine tell you what it wants.
THE Engine needs; drives the producer gas making process.
What the engine can and will do for YOU; drives the engine systems developing.
And your NEEDS and willingness to off-ass, out-of-head, fulfill those Needs should be the driver and the governor of the whole darn thing.

Terry and Koen are OK. They ARE off-ass, out doing things REAL, and usable gas making and engine powering.
Just that different folks think and process things differently. Then out-loud thinking/speaking sound as they do.
My wife and family says that I am the worst for this. One sister will say: never ask brother Steve the time - he will tell you how to make the clock. The other sister will say: Not until he explains who made the first clock! The third sister will then chime-in: And then only after he explains the pro’s and cons of ALL clock designs!

Ha! Ha! (mood lightening joke here) As I have told Koen and Terry they are BOTH WRONG!
My gasfier push improvement is for the highest within made thermalchemical methane gas production. Give the easiest controllable engine power BLENDED fuel gas. Methane is “very bad gas” tagged as 20X of CO2 as climate warming. Good thing my intent is to energy wring it out in my engine to be the safer energy spent gases of water vapor and carbon dioxide! (part of the joke)
To make this needs raw wetish fuelwood in hot active gooey hopper conditions for the moisture and the woods still active available phosphorus, calcium and potassium’s traces as catalysts for this foreced methane formation.
Kiln drying the wood seems to inhibit this formation.
Pellets heat and compression seems to inhibits this formation too.
Charcoal gasifing makes virtually NO thermalchemical methane no matter how hard you try.
So I forge on making my smooth, smooth running blended Irish Whiskey fuelgas.
Koen making his more pure clean hard biting Kentucky Bourbon charcoal gas.
Terry now stepping up from straight forward Kentucky, to making Canadian blended whiskey fuelgas now.

These WILL ALL run internal combustion piston engines.
So it is all good.

Steve Unruh

Now that is something I can relate too!