6 hours I forget if they all had exhaust. I think there might have been a flare run in there too. It was a learning experience. It totally slagged the lightweight firebrick too…
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Quite often we learn by failure or mistakes. Why are you giving up on the gas producer in the Ford in favor of the Model T???TomC
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Are those Clinkers?
I thought this through.
If I made a double wall tuyere with with mild steel pipe and blow steam in it this might be able to cool metal enough.
Best place to make a variable amount of steam would be off the engine exhaust
Make the tip out of a red brass bolt that has had the centre drilled out.
You could make different sizes depending on the need for the gasifier.
This won’t spal or burn provided there is enough cooling provided by the steam vented between the inner and outer wall
to keep it cool.
And of course vent the steam back into the incoming air.
Copper is an excellent conductor of heat it this might be an advantage.
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As far as I could tell it was the stainless mixed with char and some slag…
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Hi, Tom! ( Tom @23)
There is no “plate”; you see the bell edge line, as all drawings have where cylindrical objects end…
Max
Good comments from Chris, Tom and Ray!
The hefty blast cuts down to 4–8" below the bell-edge.
Into a “pocket”! Gas return through the sidewalls up.
This is not a “single-linear” passage “forward, forward, forward” from A to B.
It is a recirculation process, where the injection air blast (not floppy!) sucs lots of gas from the cavity under the bell for re-treatment and re-reduction.
Tom is quite right! Heat passage from hot gas to cold gas via a metal wall is not critically intence.
Especially, as the cold gas (air) has a manifold velocity compared to the (surrounding) hot gas.
High-glowing charcoal is on the other hand intensively radiating, and that’s the reason for heating metal IN THE CHAR, as blacksmiths do!
We can avoid that, by injecting the air into the “coal” and saving the blasting nozzle, keeping it outside the inferno.
In a downward shrinking pile of char, there are no other ways of keeping a controlled distance between the “dancing” char-surface and the nozzle-tip than establishing a cavity with a local, selfregulating avalanching surface.
“Dancing”?
If the bell diameter is squeezed into “small & nice”, it will be clogged by char, blown up by the return gas.
Then you loose the natural avalanche property…
Modesty & reason!
Max
Hi Max,
Glad you found the discussion.
A few folks have pointed out the concern that this design can only make CO2. Can you help explain this?
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Hi, Chris!
Perhaps the idea of forceful blasting downwards, and sucking “old” gases with the air beam is strange. Injectors and ejectors have been used over 200 years, but seems to be hard to “consume”… who can configure that?
Max
Hi, Chris!
Yes, some seem to think of “surface blowing” instead of deep penetration. Have I the right impression?
Max
as long as the exitting gas comes in contact with “new” air / oxygen, that gas will burn to CO2 and release all the heat it can. Been there, done that…
look up for “blast furnace” technology’s
As for the “cooled” nozzle’s…
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Hi, Koen!
You are right! And that is the full intension!
Airblast down into the charpocket as ready mixed with gas gives a real hot reduction “paradise”!
Max
OK, maybe this will help. Let me say first I don’t fully understand but I’m getting there… 
First off, the nozzle can’t be too big. Otherwise Koen is right, the excess oxygen will create CO2.
But what if there’s a restricted amount of oxygen, that is all sent forcefully down into the char?
This oxygen will react with the char, first making heat and CO2. This will rise towards the exit. Uh oh!
But as it blasts down, the oxygen stream “pulls” some of the CO2 downward into the char bed. Each CO2 reacts with the heated char, to make a pair of CO molecules. This also rises towards the exit. Now we have a mix of CO and CO2.
So we have created a circulation pattern, CO2 goes down, some of it is converted to CO by hot char, rises up again. Now the gas is a little richer in CO and less rich in CO2. At the same time, more CO2 is made, from the new oxygen in the stream.
This circulation happens very very fast, in fact char is flying around and breaking down into smaller pieces, which increases the reaction rate.
What must be determined is, can the circulation pattern convert CO2 into CO faster than the oxygen is creating new CO2? I think it can. I suspect it has a lot to do with the velocity, the size of the char, and the reaction temperature.
If the CO is created faster than the CO2, you will wind up with a high percentage of CO that actually exits the gasifier. No it won’t be perfect, but no woodgas is perfect. All char-gas and woodgas contains some CO2.
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I would think that this nozzle and bell would have to be raised a foot or more off from the vessel floor?
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All most like a fluidized bed reactor. Could be tricky to tune.
A little off topic, I found a nice coal scuttle at the hardware store. Made in Canada and a real work of art. Think I’ll paint it black.
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Looking at Koen’s drawing I see how the steam is regulated by a crude valve.
This could be refined a little by this sort of valve to direct more or less steam according to throttle position…
This is not quite the same idea but imagine a valve to regulate how much steam is allowed and the rest could be vented to a condenser and returned to the tank.
https://images.duckduckgo.com/iu/?u=https%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F9%2F99%2FSlide-valve_cylinder%2C_section_%28Heat_Engines%2C_1913%29.jpg%2F280px-Slide-valve_cylinder%2C_section_%28Heat_Engines%2C_1913%29.jpg&f=1
Hi Chris,
the sole problem , imo, is that the ascending gas comes in contact with descending air and wil burn into CO2 before it leaves, hence it will burn all the way out…
reactions tend to take the path of least resistance
imagine the following: the oxygen from the nozzle gets depleted by the combustion with hot swirling carbon , before it gets blown in the char, selfbalancing…
but the gas, blown down in the char would be sufficient hot to gasify the charcoal… forming CO
So, might be difficult to control and bring in balance, but seems plausible…
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Hi guys; I was thinking, after I read all the comments and re-reveiwed Gary´s videos, and I thought: …what if the nozzle is made conic itself made of refractory material, just like the exhaust of a rocket? …I think it would solve the problem. We have used in making ceramic (pottery) in my wife´s ceramisc studio, we have come up with a reractory formula made of clay, caolin, saw dust and guaba seeds, thats resists up to 1180 degrees centigrade (oC). I´ve made kilns in 55 gallon drums with it. At the moment I´m in Valencia (center part of Venezuela), next week, when I arrive to the farm (in the Andies), I´ll take pictures of the kiln and will upload the formula. I think it´s worth trying.
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I’ve been thinking about this more and side with Koen. A big MAYBE it could work, but if it did would be hard to apply to run an engine. Remember the air is being “blasted” into the char so right there you need a pressure vessel to run this gasifier. 25psi? 50 psi? 100 psi? As this high pressure air blast descends into the charcoal, the charcoal will get blown all around. Some of this will hit the air stream and knock it about a bit causing oxygen to hit the hot char as well as the hot CO. In otherwords, there is a good chance there will be some blue flames burning in this cone. That makes CO2
Take the same nozzle and pull a vacumn on the gasifier, much like an engine would pull. The air comming in the nozzle will be a much lower velocity and not blast the charcoal apart. If the exit for the gas was at the side of the gasifier, then the hot CO2 must then travel through a bed of charcoal making it into CO. The exit cannot be a counter flow as shown in the diagram. It must be from the side or top to force the CO2 away from the incomming oxygen.
That is the idea I’d like to try,
Tom, the gasifier on the model T is a kalle style. the Model T is a fair weather truck so I may as well experiment on the Ranger with this design.
Gary in PA
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OK, Chris!
1.03.2016
Here are a lot of phenomena and patterns to observe!
I bet you have never blasted (modestly) pressurized air down into a pile of charcoal?
That would have made it possible to see how the penetration hole developes, and see how avalanche char slowly forms a downsloping funnel into the center.
This same happens from the bell-edge downward.
Does the formed gas from below the nozzle-tip in the Källe creep up along the nozzle tube?
No.
The return gas spreads largely out before (a part of it) enters the circular gitter (grate) around the nozzle-tube at the co-axial exit tube.
The rest of it goes downwards along the nozzle tube to join in for a new round again…
…
So the return gas from the NARROW-throated pocket goes out through the leeky sides and will eventually rise to the cavity under the bell.
…
In the bell cavity some members seem to totally forget the property named “flamefront velocity”!
The downward nozzled airbeam acts as an injector beam down into the narrow-throated pocket cavity.
It rips ready made gas with it down into the cavity.
At a velocity >10m/s the air-gas mix “has to wait” for somewhat slower turbulences down in the pocket…
It is hard to show more than a skin-thick surface flame on the air-beam at these velocities…
Max
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Hi, Jim!
1.03.2016
You are observant! That is good precausion; with an ashgrate near the bottom, shaking out ash and small is easy, without emptying whole the “bucket”… through a side lid.
Max