hi clarence Yea if you shoehorned the cummins and got it in there you have a good engine the slang is power JOKE although i did much testing on IH power strokes that is the 7.3 the 6.0s are boat ankers but the 7.3s were very durable but not the engine of a B cummins
I think if i can remember right the P strokes are about 17 to one which is about as high as you can go
As far as complexety it’s pretty simple i’m in the process of digging out the paper work on it as soon as i find it i will post a diesel on pilot injection is really very forgiving on mixture way milder then spark ignited
but you still have to use some diesel
Tom
It seems like a OLDER 5.9 cummings with the mechanical injection and a 17 to 1 compression might be a Good choice?
Would it be a even simpler convertion? Ive read that it takes only a 5% pilot injection to make things ignite But how is the engine power governed/ do you ALWAYS inject the sameamoount of fuel in each revalution and control power with woodgas restictions? Do you have to make the amount of diesel injected bigger and smaller to control RPM?
Hi Rodney
You still need to use a throttle if not when it hits the gov it will stop igniting and when it slows down and relites it will be like turning the key off and on in a gas engine GOOD engine to convert much tuffer and better torque then a power stroke
good luck
Hmmm. Let me expand on this a bit.
Dedicated diesel you do NOT have to control an air to fuel ratio for even steady combustion. Woodgas fuel, like gasoline you do.
Too much air for the amount of woodgas fuel pushed or sucked in and it will not lite off with either a diesel pilot ignition or a spark ignition. Lean miss-fire.
Not enough air for the amount of woodgas pushed or sucked in and again the woodgas fuel will not lite off and in the cylinder combust. Rich miss-fire.
In both cases the unburned woodfuel gas and air will be pumped out the exhaust not yet combusted.
The deisel govenor if still active will rack up more diesel flow to try and maintain power and RPM. If diesel rack is limited engine will lose lots of power/RPM and may even die.
This is one reason why once you are primarily fueling with woodgas you would have to control the air to the actual amount of fuel gas inducted. Or visa-vesa. And the combined system better be good, and able to control now the diesel, woodgas fuel AND the air through all operating conditions.
Those who have done this report a big problem with engine run-a-way speeding up with sudden engine load releases. AND with engine load changes like generator load shedding, or in a manual transmission, having severe back firing out the exhaust.
Sorry. Not going to be easy and straight forward like methane and propane fumigation fuel supplementing a running diesel. These are both respectively ~5X and ~10X as energy dense as woodgas and pure hydrocarbon fuels. Not nitrogen and carbon dioxide diluted like woodgas fuel.
Methane and propane are both PRESSURE supplied to the engine.
Most woodgas producers are built for carbon monoxide safety purposes to be engine sucked contiously.
Diesels do not suck. Why they need to have supplementary vacuum pumps for the power brakes and climate controls in the pickup and van chassis installs.
So to retain the woodgas system suction flow you must convert your diesel to a suction engine.
You do this by controlling the air to create intake manifold vacuum.
2nd reason you will have to actively now control the engine air.
Regards
Steve Unruh
I get it. as deisel fuel sprays into the cylinder It isnt combined with ALL the air there just what it meets in the area of the injection so at some point there is the correct mixture and at others no fuel at all and thus the extra AIR is"Invisable" to the fuel mixture.
Wood gas on the other hand wouldnt be injected in a compact mass it would be more or less mixed thru the whole cylinder…
Id think it would be best to run woodgas a bit lean so that the pilot diesel injection finds a LARGE areas as possable to induce the correct combution ratio.
for instance a small injection into a cylinder filled with wood gas might be the proper amount to burn 25% of the wood gas a larger one might be enough to cause the proper ratio to ignite in 50% of the wood gas. and so on…
It woul seem that tp do this with the diesel pump controlling the process it would require a VERY consistant woodgas to air mixture and would waste a LOT of woodgas?
Hi Lewis
Yes more or less when i worked for the gov in research it took me awhile to get a grasp on it
A phd at MIT finally got it through my head all the years as a mechanic i always thought combustion was combustion boy was i in for a surprise On a SI engine the mixture has to be at a close ratio so when the plug lites it the flame burns on a micro thin layer through the charge On a diesel the cyl is full of air preheated to about 900 to 1050F.Diesel will lite at 760 to 900f or so as it is injected it burns a diesel really needs swirl if not it will smoke bad no matter the boost
When you pilot inject you have a charge of wood gas heated to the 900-1000 or so So it will not burn but whenyou inject a little diesel into it the diesel ignites and then ofcoarse the combustion event takes place
it can be taylored by how much fuel and how deep into the charge it goes the temps i gave are just ball park to many things very this to list here
MIT has a very good book on this if you want to get deeper into it
Without getting bogged down in details once you do this it becomes an SI engine only with a shot of fuel instead of a spark so then you have detonation worrys just like a SI engine Detonation is not fully understood but it happens when the flame front advances across the chamber it squeezes the mixture to the other side if it squeezes it to hard the temp will get high enough for it to lite then you have two or more flame fronts moving towards each other the gas in the middle gets squeezed so hard it more or less becomes plazma and you know what that does to metal
Sorry to string on so much but it’s pretty involved
I will post that MIT book title so if anyone wants to get it It’s a really good read
Good luck
Tom
Hey Lewis
I should have mentioned the o2 temp factor
The pilot fuel really just gets the chamber temps up to lite off for the charge
On our hcci compression ignition engines where we have ample compression temps fuel ratio goes out the window if you have an o2 rich enviroment at or above the ignition temp of the fuel regardless of what fuel it will combine with the o2 or in other words combust we had good test equipment with press tranducers and thermocouples in cylinder to prove this and even the smallest amount of fuel will combust in that enviroment
But as steve i think said you still have to control it or it won’t be useable
somewhere in the premium section i posted a simple diagram of how to do this It does work but it’s not turn key takes a lot of work to tweek it
good luck
Tom
This is what helped me understand how diesels work vs gasoline or woodgas. Bear with me as I know it’s way oversimplified.
ALL fuels have a temperature when self ignition begins. Diesel is relatively low, Gasoline is relatively high. Woodgas even higher. When self ignition happens at the wrong time, it’s called knocking or detonation.
When you compress FUEL to a certain temperature it will self ignite. Compressing air doesn’t have this effect, since it’s not flammable.
A gasoline engine compresses FUEL to a temperature just BELOW the auto ignition point. A spark then begins ignition. Many things can throw off this delicate balance and cause knocking, one being a very lean mixture.
A diesel engine compresses AIR to a temperature far ABOVE the auto ignition point. Fuel is injected at the right time, and instantly self ignites. Lean mixtures are no problem, they cannot cause detonation because the fuel is not present yet. Therefore a diesel does not need throttling, the cylinders can always be filled with air and the only variable is the amount of fuel.
When you add woodgas to a 22:1 diesel, you are compressing woodgas FUEL to a temperature ABOVE the ignition point. It will knock, same as gasoline. The explosion of the gases is no longer under control, and happens too early.
When you add woodgas to a 17:1 diesel or regular gasoline engine, you are compressing woodgas FUEL to a temperature BELOW the auto ignition point. It is ready to be lit, either by burning diesel (which ignites at those temps) or by a spark plug.
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Very well put Chris
I found my mit textbook but i need to find the publacation #
I had forgotten how dizzy it made me trying to read it LOL
After all i’m a red neck it was a real chalange in the PHD enviroment but fun too
Tom
hi tom
i started this discussion and thanks for the comments , but never did see any paper work or diagrams.
Diesel engines run by compression - no spark - the compression stroke at near 20:1 produces 500-750C near instant gas temperature - then diesel is injected - it is going to combust when the diesel is injected !!! Wood gas along with the atmosphereic air with a high compression engine and it will autoignite. How much compression? I do not know today. BUT you will still need diesel for lubrication and basic startup combustion etc Start on diesel then add wood gas. So plan on something like 20% diesel and 80% wood gas during operation. Plumb your wood gas flow regulated (good meter) to your diesel air cleaner body… I believe the best way to monitor the combustion is by Exhaust Gas Temp (EGT) guage - add a known wood gas flow rate and see if the EGT detects the change in temp - watch for autoignition - too much wood gas - the EGT temp drops etc… burning BTUs input means your diesel is doing work. Check your diesel manufacture for EGT limits. There is a limit on how much basic engine compression before the compression stroke produces to much heat and the wood gas will autoignite - what is the optimum or upper limit for diesel compression ratio to use wood gas? My International DT466 manual says this engine is 17.5:1 compression - time will tell - anyone with a portable wood gas system wishing to visit and test - let me know. Maybe others have already experience - What say you?
Here is a video on Youtube with a Perkins 6-357 diesel running on wood gas: http://www.youtube.com/watch?v=ilIENTm5muo&feature=related
Ah good you found this DouglasP.
Welcome abound the good lifeship Woodgas.
If you put Diesel Engine in the Search box on the LH side bar you will also bring up over 15 other topics where this has been touched on.
Woodgas fuel supplementing of diesel comression ignited engines has been done a lot going clear back to German government and industrial and bus/truck big 2-stroke engines back in the late 1930’s.
Pictures of this in the WWII Gasifiers section here.
Most recent documented work has been in India in the 1980’s into the 90’s. Some obscure Chinese research out there too. Before these there was some government sponsored well documented dedicated work in Sweden with a farm tractor and a delivery truck. Some 3-4 year to last year recent down in California at All Power Labs location work also.
You are correct that fuel(S!)/air/speed with variable loads controlS has proven to be the most difficult problem.
When done because of heavy oil fuel shortage abandoned quickly when those fuels became available.
With a diesel fueled cycle you only have to control the fuel quantify and the timing of the fuel injection.
With a spark ignited gasoline/propane/methane/woodgas fueled engine you have to independently control the air, the fuelgas and the timing of the spark.
Woodgas supplementing a diesel compression ignition is not like relatively easy fogging in supplemental pure dense refined 100% HC propane or methane. Woodgas at best only has 40% of the composite fuel gas as combustibles - the rest is inert gases and free soots.
Woodgas as an 80% fuel component you then have to individually now control the air, now TWO different fuel streams and the diesel injection timing.
Because of now compression limitations to 17 to 1 for the woodgas fuel so it will not pre-detonate AND now the engine having to suck against an air throttle restriction (have to now control the air for the woodgas useable A/F ratio AND create a suction to pull the woodgas through the hearth and filter rectrictions) you just lost two of the three reasons diesel CI engines are more efficient than SI engines.
The India developers found that they could elaborately vacuum/mechanically set up systems to control all now FOUR factors. Later they did this electronically. Thier biggest problems reported were damaging engine run-a-way overspeeding (same found at APL) at engine load shed off conditions (large electrical consumer suddenly shutting off and transmission shifting points) along with severe damaging exhaust backfiring.
Later still you can see the lightbulb went off and Cummins-India and the Practash engine companies there just started suppling compression reduced, magneto and ignition distributor diesel based block converted engines for dedicated woodgas (“Bio-mass”) and methane (“Bio-Gas”) useage.
Then back to only three factors to control.
This is how the industrial IC engine company Jenbacher/GE had done it all along.
Oh yes. In the past 4 years I acquired two different specialized diesel engines with the sole purpose to woodgas 80% fuel them on a CI. Then I correspond and read of those who had done it, thier problems encountered and work-a-round solutions. Too complex. Then planned out spark converting them. Still too complex and a shame to waste of two fine diesel engines. Just went back to normal IC spark ignition engines and no longer have to worry about trashing an expensive, hard to replace injector pump and onjector from too low of cooling liquid fuel flow. The problem the Swedes had on their engines after a few hundred hours. And now I can multi fuel on gasoline, propane and methane also.
Regards
Steve Unruh
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I was trying show the little VW running on wood , Maybe this is it.
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Hi Jim
Sorry i must have forgot you
The manual is MIT professional edu.program
date is july 2004
coarse #2.615
If you can’t find it send me your mail address and i’ll ship this one to you
I probably won’t use it any more if i go back to the gov I’ll have to get a refresher coarse
It’s pretty involved it explains the reason some CI engines have more compression then others
small bore/stroke engines loose more heat thru the walls and head so it may or may not really have more heat it’s not a one rule fits all
Anyway your welcome to the manual
Sorry again i forgot to respond
Tom
Hi Jim
Did you ever get the diesel to run on wood gas ?
Thanks patrick
HI PATRICK
no I never started the project , even tho I haven’t gave up on the idea.
I bought a 93 Dakota 4x4, using it for the first build.
Hi Jim
I have been doing a lot of reading up on diesel gasification, both Victory gasworks and Trillion gasifiers both say they can run a Diesel engine with out modifications on wood gas.
Just search youtube on trillion gasification and you will find a lot more videos.
Most of the engines seam to be turbo charged and running constant loads, water pumps or big generators.
Thanks
Patrick
Hey PatrickJ.
I actually worked in the VictoryGasWorks Developement shop for a couple of years. More than any one thing I was Steve the Engine Guy.
To fuel a diesel on woodgas the compression ratio has to be below 17/1 to prevent loaded pre-ignition in the cylinder gas explosion events. Well right there that eliminates 90% of modern diesels and only a percent of the old lower compression diesels are possible. Then they cannot have rotary injector pumps; even many inline injector pumps proven to need added on modification to the fuel bypassing at the least to cut down on the low diesel fuel flow now well dicumented overheating and accelerated wear issues. The individual unit types injectors systems seem to be the easiest to control and accommodate. So even more diesel engine types eliminated. And you really do not want to run normal spark engine allowable filtered woodgas through a close fitting GM/Eaton rotary lobe blower for long. So out with all of the GM 2-stoke blower pressurized diesels out there. Or onto to unnecessary 3rd and 4th stage expensive elaberate woodgas filteration.
Now that seems to be constant load thing is true - changing loads has severe engine overspeed problems on load shed offs especially by going rich on woodgas and exhaust back firing. So more mechanical or electronic controls needed added to be able to quickly slam the woodfuel on and off or add exhaust air to dillute and cool. Documented.
Then on the turbo’s. Most do not like at all to have suction on the inlet side. Pulls cooling/lubricating oil past the turbo shaft seals - the diesel will love running on this heavy oil “fuel” - back to an engine over speed problem. Documented. So IF you are going to engine suction draw safe the gasifier system as 99% do then you have to change out the turbo for one able to handle suction. OR you can have the whole gasifier system either pressure blown or external of the engine sucked with the woodgas then mildly pressure delivered to the engine like is done with LPG and NG gasious fuel supplemetaion system. Forst off will take a few kW/me or kW/electrical to power this now constant operating high flow capable gasifier blower system. And then the varying fuelgas needs NOT THEN being matched directly by the engine itself, but now having to be calculated and matched metered will need a whole 'nother system developed, built and added on to control the acutal delivered woodgas flow.
Ha! Ha! Made my biggest woodgas “KaBooms!!!” every were working on pressure delivering!
And I haven’t even covered the combustion/ignition/timing issue differences beteeen the different IDI and DI diesel systems out there.
Anyhow it gets alot more complicated quickly to be acual daily load varing useable than just stuffing a woodgas hose down the air inlet on a diesel engine
Bottom line is the actual experienced diesel engine companies with paid development engineers fueling with woodgas like Wakashaw, IHC, Caterpillar, Cummins/India, Pratash, Mitsubishi and GE-Jenbacher all just spark converted, lowered the CR’s into the 13/1 to 15/1 range on their diesel block based engines for woodgas to get around all of this extra needed development and expense and added multiple systems maintance.
Yeah I watched your Trillion Gasifiers video.
Lots of ooh-rahh videos out there. Cameras are cheap and Internet vidoe requires no other proof or “the rest of the story” results like peer publishing. I’d want to see anything after a minimum of 500 hours variable load run time. Then 5000 hours of across seasons annual results like all of the mainline engine companies will supply on thier spark converted woodgas fueled setups.
Just can’t seem to get this particular Internet myth killed no matter how many actual done-it, tried-it documented written references I’ve put up. Sigh.
If it ever sounds too good to be True - then it ain’t - True that is.
Regards
Steve Unruh
Hi Steve
I have just found your reply.
So you are saying in a nut shell, you can add wood gas to a diesel but the injectors will over heat ?
If its turboed It will eventually errode the intake impeller of the turbocharger or blower and or suck the oil out of the penstock .
Then there is a timing issue as well !
I contacted Trillion in Singapore, thinking I would import their units for the friend of mine farming in Zambia.
They assured me that a diesel would run perfectly fine on pilot diesel injection ignition and wood gas.
So in your experience its a load of BS ?
I’m inclined to believe you, you are not trying to sell me 8 gasifiers!!
Thanks
Patrick
O.K. Patrick one at a time.
The actual diesel injector is inserted with direct contact into the cylinder head and protuding in some way into the hot combustion chamber or a combustion chamber connected pre-chamber. At normal diesel engine idle not much engine cylinder head heat produced and not much cooling diesel fuel flow needed to suppy. High engine load on deisel; then high volumn of diesel fuel flow supplied to the injector to fuel the engine and injector heat remove. Low “idle” amounts of diesel injector flowing with HOT fully loaded cylinder head temperatures documented DID cause problems with the 70’s Swedes projects, the 80’s,90’s in India projects. They had to modify to incease the actual injector bypassed fuel flows to help cool the injectors to reduce accelerated injector mechanical wear, heat warpage and seals failures.
The actual diesel engine companies with professional paid engineers measured THIS problem challenge along with other found needed adaptive durabilty/cost factors and all decided to just ALL go with spark converted compression adapted engines when they were direct engine system suppliers for producer gas systems. Thier name/reputations were on the line.
Woodgas most certainly CAN be turbocharge boosted. Noboby done it has complained about increased impellor/turbine wear.
You have any old many hours gasoline or diesel turbo’s engines around in some working application? Ones that have worn the turbo shaft seals now constantly drooling oil out the air in snorkel? OK with the engine running and loaded into turbo boost range restict the air in side enough to produce some negative pressure on the inlet side. Now watch how much oil you will suck out of those turbo bearings! IF a diesel careful of engine oil fueled speed run-a-way. Have an inlet strangle plate handy!
Engine sucking a gasifier system you WILL be doing this inlet side negative pressure operating 100% of the time or you will not be getting any woodgas produced to the turbo to go to the engine. So as the Finn Vesa Makinen here on the DOW posted up from direct woodgasing experiences you need a turbo that has oil bearing seals of a type, unworn, that CAN take this woodgas system negetive pressure on the inlet side.
Now since obviously I, both VesaM’s, JonathanL, WayneK, and a whole bunch of other Sweeds, other Finns and India fellows along with 7 mainline very diesel engine capable, engine manufacturers are so full of it (fecal matter) saying these things then it should be no problem for the Trillions/Singapore people to supply you with the direct independent contact info of 3-4 actual in the real world user installed systems in current use with accululated 500-5000 loaded hours fueling diesels so THESE independent satisfied system users can directly sing thier praises.
I’d really like to hear about these actual in the real world satisfied pilot fuel diesel engine woodgas users. Please ask them for thier engine types: 2-stoke, 4-stroke; IDI, DI; natural aspirated, forced induction; fuel injection type - rotory pump distributed, inline pump, individual pumped, unit rocker arm type or electronic common rail.
Then we can sort out which of the many actual diesel system types out there that these real users are satisfied woodgasing with.
Regards
Steve Unruh