Hi Tom, I used a magnetic switch from the starter, I’ll see how it works during operation. As you can easily see, another 12V relay is connected, which disconnects the magnet in the upper position, and the spring pushes the core down, …
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Silencer and air heater for additional drying of wood chips, …
I also tried to operate the asynchronous generator independently by connecting capacitors, the thing works, but a controller will be needed to control the voltage
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Today was a beautiful day in our places, but I took a short break from green energy production, I burned charcoal and filled it with wood chips from spruce branches, the generator was just bouncing off the power, …
https://youtu.be/LhS3X7DeoO4
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Fully functional!
Any idea about diesel/ wood ratio?
Condens from exhaust gas? Cool!
Do expect problems with heat exc caused by condensing?
Did you fix the problem to shut the generator off when there is no power generated?
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Hi Joep, today the system operated for 4 hours and consumed 1.5 liters of oil and 15 kg of wood, constantly producing around 4 kW of power. The magnetic on / off switch works and turns off when the current drops below 1A, namely I added capacitors to compensate the reactive current (3 x 30 mF connected in a triangle directly to the motor), the current in the conductors decreased by 5A. My son Domen is trying to program a controller that would control the system, namely the mixing ratio based on the lambda probe, interval shaking, disconnection from the mains under conditions of low power, high temperature, maybe even a lambda signal. I do not understand what you mean, problems with exc heat?
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Supersystem. I love your aproach. Impressive!
You let the exhaustgases go through a heat exchanger to dry the wood? Does there condensate the exhaust gases? The 6 mm airline that is dripping?
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Yes, the exhaust gases cool down and the steam condenses and drains down the pipe, … the last waste energy for drying.
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Keep us posted Tone, running everyday? How are the controls doing? Fuelpump is set to max 10% or can it jump to 100% if there is no woodgas?
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Joep, I don’t start the generator every day, I’m a little afraid of the night cold, because I have water in the system, I have to make an isolated space in this place … I open the diesel pump only at startup, then limit the fuel gasifies in the nozzle itself and an air bubble forms in the system, then the engine loses power because there is no good ignition. The diesel limit must not be less than approx. 10%. As I already wrote, the asynchronous electric motor works well with the mains, and with added capacitors (3x30 yF) we compensate for reactive current and can also operate independently, only that the capacitance needs to be adjusted to consumption, which I have not done yet.
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Let me bother you a little more with my view on the shortcomings of the gasifier, namely the increase in resistance in the reduction zone and the problems at low load. In petrol carburettors this is solved with twin nozzles , the first small ones are for idle and the second large one is for full load , but I wonder why not use this in a gasifier ? I think that would solve a lot of problems, you may remember that I have already posted this sketch, but twice is better than never.
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Must ask, to come in from below with the air, do not you cool down the reduction then?
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Jan, if I analyze a little, the air coming from below is already quite preheated on the branched grille and at the same time the exhaust gas cools down, I will probably make an even larger grille for the next construction, so the grille is also an exchanger. The central nozzle will be made of a hollow drill for drilling stones, the inner hole is 7 mm, otherwise high-alloy steel is temperature resistant. Given the preheating of the air in the area under reduction, I do not count on a drop in temperature in the hot zone.
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I think it is a great idea, Tone. This design of yours might be more sensitive to an optimum size of wood chunk to prevent “constipation”. 
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Thank you Tone. Looking at your drawing I see what Mike is seeing. To little of a restriction opening for Charcoal and fines to flow through.
Let’s talk about the restriction opening, and what is happening here in milliseconds at this opening. This is a very vital point in gasification. It is a high frequency point, vacuum point, heat transfer point, and magnetic point for the gases and their structures to go through. Now we know some gases are bonded to together stronger then others. We will just talk about two gases right now that we are changing. H2O and CO2 in to H2 and CO. I am sure you and everyone knows that the Oxygen is removed from each. The important thing is the flow of Charcoal and fines ash needs to be a continuous movement through the restriction opening with out stopping. To put a picture in your mind. Think how lava flows. I am sure you have seen this on videos. That is what’s happening inside the gasifier. The Air/gas velocity is changing higher and lower all the time.
So looking at the drawing and you will see what Mike and I both see. A spot where all the things above can stop and plugged up. It needs to be larger at the restriction opening.
The drill nozzles is not helping with the restriction opening going up through it.
How about moving the restriction opening up to where the drill nozzle ends and make the pipe and opening larger and changeable for sizes.
Bob
Edit: also I don’t think the center nozzle will hold up to the heat that it will be subjected to. It will probably melt down. The Charcoal is white hot in this area. 2000 to 3000 degrees f.
Bob
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I think someone forgot about such a state of matter as plasma! 
In factory gasifiers for trucks at 100m³ / h, produced in the USSR, there was a limit of only 82 mm and no one complained about constipation and insufficient power (compared to a limit of 150 mm).
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My idea of what happens in the hot zone is that pyrolysis takes place above the glowing embers and pyrolysis gases are produced which rise up the middle below the top and return to the glowing ember zone along the wall , in effect this is how the wood is cooked into charcoal which slides down , these pieces of charcoal gradually get smaller on their way down , as carbon is consumed in the reduction. The smaller and smaller pieces of charcoal mixed with ash will slide towards the restriction orifice where the gas velocity is highest, so this should allow the condensed fragments to move through the restriction orifice as well, but only if the charcoal is still glowing, if it stops glowing higher up in the fire tube, the condensation of the charcoal and ash under the flow of pyrolysis gases will cause a blockage occurring high up in the fire tube.
That’s why it would be good to have the air inlet close to the restrictor and also close to the centre , so the charcoal would always glow in that area and even if too much air came in it would be used up down on the grate to outgas the charcoal dust , a similar effect is used by a Swede in a separate room on the grid , Jan has attached a photo of this somewhere.
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The only way is to build it and test it out on this new design concept. I can hardly wait to see the results. This gasifier will be many pounds of weight lighter which is great for small vehicle cars and trucks
Yes what you said about what goes on above the nozzles is happening.
I have shut my gasifier down after a long run and let it cool for a while so I could look into the top of the fire tube with out so much smoke. Open the hopper lid and let the heat out.
I carefully looked inside with a face heat shield and poking around just above the nozzles were wood brands and not fully cooked into Charcoal. Right at the nozzles it look like Charcoal. But this is my WK firetube. Closed it up by next morning now cold and opened it up the wood brands were now Charcoal just above the nozzles and wood brands were high into the hopper. It would have been more so. If I had not let all the extra heat out. I have done this a few times. Just call me a curious guy and like to observe things that people might not think to look at.
So the gasification cycle starts when wood enters the hopper and ends after the grate or griddle and falls into the ash box. Looking forward to seeing more. Keep asking the questions this is a great thread.
Bob
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Tone, l have done this before
Worked just as good as any other similar sistem. But the way l look at it its actualy possible for this kind of a gasifier to be more dangerous, tar wise. The lower nozzles rob the main jets of air velocity, so more tar can slip trugh the charbed.
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Hello Tone,
I’ve linked to Bob Mac’s explanation.
And he had linked to yours.
Your’s was an excellent explanation of the physical movement processes that must take place within a wood fueled gasifer.
Very good, and clear English by the way.
However . . . your proposed design is too complex for the long term needed temperature environment that must be maintained; to get to; let alone exceed the best practices, peripheral jets gasifiers 72% conversion.
Before metals will crack and fracture: LEAKING!!, they will heats distort change. This changing, disturbing carefully set dimensions.
The two ways found to actually move the woods cell walls freed up mineral ash is gas velocity, blow through, transport.
Or: leaving enough fine sized pea charcoal to allow the ash then as a composite, to flow.
Ash not transported quickly out of the intense heat reduction area will melt forming clinkers.
Then the whole process flows chokes off.
With base woods from under 1% mineral ash to above 7-8% mineral ash it is very hard to manage this one variable in a same use design.
It is the Operator wood sizing; mixing wood species; and by engine RPM and gasifier loading who accommodates variables.
Better than a gasoline carburetor comparing, compare to working piston steam engines.
US/Canadian/British/German used single expansion steam for rail. They had the domestic coal to use less than ideal. Simplicity, durability, was King.
The French did not have the coal to waste. They had to evolve to much more skilled Operator live tuning double expansion rail steam engines.
For large Ocean steamships, they all had to evolve to best efficiency, triple expansion steam engines. No coal deposits or mines out in the Oceans. These systems needed then at least three levels of skills to operate. Oilers/wipers. Fitters/artificers. Master operating Engineers.
DIY wood-to-shaft power best, easiest, to become a better Forester, imho.
Wood for energies is a true Rural thing. To have the Land; to have the trees and brush.
Regards
Steve unruh
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Thanks to all of you who are contributing to this thread, Kristjan you have done great , but the difference is that in the proposed idea the upper nozzles are switched off at low gas consumption, or rather, the float valve in the airflow shuts off the air flow, so the air only flows to the lower nozzles and the temperature is kept high in this reduced area, but when the flow rate is increased, the float valve in the airflow rises and opens the passage to the upper nozzles. I am even thinking of making a smaller WK below with separate air inlet instead of a centre nozzle, thus creating a double WK, small in large, for a wide range of loads.
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