You could preheat air in other places, then. I forget if you wrapped an exchanging jacket over the cyclone. Maybe around the cyclone and then around your muffler. I would leave nozzle and restriction the same size to see how performance is. Changing one variable at a time to reduce the mysterious X Factor.
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I had preheating between the unit and the cyclone before, but noticed no difference.
I believe more that the pre-heating makes it possible to insert larger restrictions and nozzles, without tar and save some wood, (but thatâs just what I think.)
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From what I understand, pre-heating dictates how wet of a wood you can use.
Imbert had theorized if he wrapped an air jacket around the hearth as most do now and am external air jacket around the gas jacket he could use 30% moisture content wood. It wasnât economical to do that in a factory production since he was already tooled for what he was making during the war.
Picture a wartime Imbert with the heated hopper, but with an additional jacket around that to preheat air. It increases efficiency and decreases wood consumption. It is allowing the gasifier to bring in what would be wasted heat to dry the wood.
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Iâm having a bit of a hard time understanding, (Iâm bad at English as you know) could you make a picture of what youâre saying?
It sounds interesting.
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Sorry for the crude drawing and Google translation, fresh air enters at the top of the outside jacket and makes its way down to the bottom and is piped to the air jacket around the hearth and finally to the nozzles.
It still has a heated hopper because the hot gas jacket envelops that and still exits from a high place to let soot settle out.
That line I scribbled over is an error.
But this is what Imbert envisioned. I think a monorator would still benefit the design.
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Thanks Cody.
I have never seen it before.
In the book that I bought from Niklas, the Swedish state between 1951 and 1963 had tried different amounts of insulation of the wood container, they got the most water from the wood with uninsulated container.
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To me the wood gasifier needs a hopper to hold the wood and let the moisture steam come out with heat from below the firetube and the condensation to be cool to water and be taken away from the wood to a condensation tank. As the wood moves downward it pyrolysis down to Charcoal as it enters the top of the 12" firetube where it comes into contact with the nozzles blasting 600°f air into the super hot lobe of fire below the nozzles where the reduction of charcoal being done. This part of the firetube is pulling heat away by it design and heating the preheated air up to the nozzles highest temperatures that can be maintained. Thanks to the preheating stages. The restriction zone on down to the grate is the final area where the gases are made from one to another. Also this area of Charcoal is the Charcoal reserves for maximum pulls on the now Charcoal gasifier will a super hot wet gases. These gases now need to be cooled down and the moisture be brought to condensation point and removed from the gases.
Doing all this process with as little vaccum as possible. Also removing the ash/char and most of the soot too. The WK Gasifier seems to be able to this be cause of it design built into this.
Bob
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I looked at a few different ways to preheat the air yesterday.
I found this picture of an Imbert in my old book, they take in the air and let the outgoing gas and fire pipe preheat the air.
I understand that outgoing gas is good to preheat with, but is it so good to take the heat from the fire pipe?
I think itâs hard to see, but outgoing gas is dashed and incoming air is dotted.
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Several questions (bored when itâs so cold) can you maintain 60mph on a 3-4% uphill which is around 0.15miles on just wood gas?
Jan, we all try to achieve as little heat loss as possible during gasification through physical design, so that the air intake for the processes is small and the gas is strong with few inert gases. We lose a lot of energy when drying wood and condensing excess water, but this is of no use to us because it is at a low temperature, and the hot gas produced, which, as soon as it leaves the hot zone, is supposed to preheat the fresh air to a rather high temperature ( 300-500°C), well, the remaining heat is given off for heating the funnel - help in drying the wood and heating the pyrolysis gases, which descend towards the hot zone. The fresh preheated air travels along the walls of the hot pipe, which indeed steals some energy from the process, but the more it is preheated, the less it takes here, but still this is enough to prevent the fire pipe from overheating. I believe that here the air heats up to over 600° C , which is great for blowing into the gasification process of charcoal or wood. Let me add one more thought, the hot generated gas, which probably has a temperature of 600-900°C, quickly loses this high temperature because it reflects to the surroundings and only lukewarm heat (300-400°C) remains, so I am trying to install a heat exchanger right at the exit from the hot zone, this Imbert model has already lost its highest values.
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,Ok, thanks Tone.
That explains this film that I usually watch (@Chris you can remove it if itâs secret) I was so surprised that incoming air went past the fire pipe, but I know that wk had problems with the fire pipe getting too hot.
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The joy of experimenting.
WG-miles vs time and effort - ratio.
Personal preferences.
Me personally, I rather spend my time and effort on the fuel (read moisture). Every bag of chunks I burn has been sitting 6-12 months in indoors heated space (after drying outdoors). It suits me personally to put some extra effort into wood handeling, which I enjoy. I try stay out of comlexety as much as I can, which I donât fancy as much. I try to save some time effort in that end instead.
Tone, youâre right. The closer to the fire the hotter it gets. This is why I believe we get the most bang for the buck by focusing on the heart and fuel moisture. Iâm pretty sure boiling off water and to super heat the steam requires more heat than we can ever transfer into the incoming air.
Remember, thereâs no right or wrong here. Youâve got the skills and equipment. I try to make do without. No mig, plasma, hydraulics and so on - mostly because I hate the hustle of storing and maintaining equipment.
In short - I prefer the smell of freshly cut piss willow before welding smoke 
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Yes, but will there be any better effect?
You know I tested my wood which I thought was dry, it was 17% on the outside of the bag according to the meter, but the pieces I tested from the middle of the bag weighed 40 grams and after 2 days on the element they weighed 20 grams.
I didnât notice any difference on the car with that wood or the wood I made on old dry boards.
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The better effect will be less power loss than if your wood was too wet without the preheat.
In an Imbert it generates that heat with the fuel to dry itself and the monorator removes the moisture from the system. But that requires specific velocity and thatâs been accounted in the size charts and formulas.
Preheating has been known to increase methane content and reduce nitrogen content. So yes I think thereâs a power gain if you preheat the system.
But personally I think an Imbert/SMP with a monorator is already very efficient.
From what I have learned from the WK and other systems that preheat, you want to heat up the air from the least hot to the most hot. Like how JO has his Volvo preheat going from the exit side of the drop box and then to the hearth.
Like say, muffler exchanger to a cyclone and then to the hearth you arenât going from hot to cold to hot, youâre going from Warm, Hot, Hottest.
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Hmm, I who thought that the warmer it is, the less methane?
Yes, that would probably be good with
preheating, if nothing else to protect the tar, Iâm a little more afraid of it after my adventures with the Iller.
However, I believe that @TomC tested quite a lot of insulation and preheating, and didnât get much better results.
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I donât mean to say this in a disparaging way but I think Tom Collins did too many changes at once, at least thatâs what I noticed reading that thread. But that happens a lot when you experiment. I am glad that I am a slow worker and also lazy.
I think in your personal case with the S10, youâre driving a truck about the same size as the Dodge Dakota but you have a smaller engine. I wonder how @Woodrunner performs in his full size truck with the 6.5L on the hills, and compare it to Tom Collins full sized truck with the 4.3L. I know Tom had said when he added preheat and the other improvements his top speed went up, but I think he pulled too hard on the gasifier and consumed charcoal too quickly? His average best cruising speed before the additions was 55 MPH so around 90KM/h.
Are you having a hard time with maintaining 100 kmh uphill?
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Yes, itâs impossible, I can keep 80kmh about 50mph if the car runs well, on these hills
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You might have to hybrid in gasoline when going up the steep hills. Wire in a 12v Pulse Width Modulator to the fuel pump to make it trickle the gasoline in. It would take finesse and adjusting the air. I think it is more the issue of the 4.3L V6 and less of your gasifier.
I had the same issues in my Mazda, my highest speed with my 2.0L engine was 45mph uphill, and 55mph on the flat roads.
Sorry but I havenât been following the Driving on Wood but I did get a notice that you had mentioned my name. Yes, I did a LOT of testing with different configurations. I donât know what you have been talking about on this thread, but I have to say; all of my building and testing was to get more speed out of my truck. A lot of my tests were just a drive down the road abot 5 miles and I saw no improvement in âspeedâ, so I went home and started working on another change. âSpeedâ was the only factor I evaluated. Some of my changes may have improved the gasifier in other ways, but if âspeedâ wasnât improved, I took it apart and moved on. TomC
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Tom c, you got the car running very well with the wk style you did, do you remember what size restriction you had?