Jan , you already have the lower part of the storage tank somewhat insulated as the funnel limits the radiation outwards and the gases travel down the wall and inwards towards the hot zone. Part of the water vapour condenses at the wall and the rest continues towards reduction. An insulated top would improve performance , especially in cold weather.
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You probably know the story, but anyway, it goes something like this:
My husband drives the car to the foreman:
Master , my car is not working well , can you see what is wrong?
The Master lifts the bonnet:
Start the engine.
He tests the operation for a while, then takes the hammer and strikes, the operation settles down and the engine runs smoothly.
The man happily asks the master:
How much do I owe?
Master:
100 Euros
My husband was surprised:
How 100 Euros, since you just hit it with a hammer?
Master:
It costs 1 Euro to hit, 99 Euro to know where to hit
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Tone, wood is not pure cellulose but for the sake of simplicity lets take it as such. Lignin has a similar constitution anywaysā¦
Cellulose is C6H10O5. Its called a carbohydrate wich literaly means its composed out of carbon and water. So, we can also write it like this
6C + 5H20
If we look at the reaction that happens in the gasifier, wich is
C + H20 - - - > CO + H2
And take in to count the always present wood moisture of 20%, so adding a nother water molecule, we get a formula like this
6C + 6H2O - - - > 6CO + 6H2
Now, this all looks fantasic! In theory air dryed wood has the ideal ratio of carbon to water. But, the reaction is endothermic. It uses up around a third the energy that wuld be released if we wuld burn the wood completely.
So, we need to sacrifice one third of the energy contained in wood to keep the reaction going.
In the world of gas chemistry, equal moles mean equal volumes. If we look at the top reaction, we see that theoreticly we shuld get a 50/50 mix of CO and H2 in our gas but in reality the ratio is about 70/30. It is here we see the effect of the endothermic reaction in real life, not to mention the heat losses.
This points us to the opposite direction. We want to eliminate some water from the equation in order to lower the energy needed to fully convert everything. Condensing some water out is one way, but we must keep in mind that water first needs to boil out of wood, then it needs to recondense out wich again requires a lot of energy that we desperatly need.
We can put some energy back to the sistem via heat exchange but still it isnt enaugh.
Mixing 20% of charcoal in the mix works for me, as it takes care of that water excess, but l understand its not an ideal solution for everyone
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Correct this if my rough maths are wrong.
True that wood moisture released in-hopper takes heat energy then lost to condense to out.
BUT . . . moisture condensed out after passing through the hearth/restriction/grate area will be ~3X the heat energy lost because that moisture had to be superheated to a minimum of 600-650C.
Always better to remove moisture in the hopper.
BEST to reduce excessive moisture before the wood goes into the hopper. Used year around; this is not always practical.
What is practical for stationary systems is to use every normally blown-away gasifer system downstream BTU/heat-joule to pre-dry and warn the wood. Use IC engines wastes heats too for wood pre-conditioning.
A fellow with an overly simple gasifer hearth using all systems heats for benefits will performance run ahead the perfectionist idealizing over each and every step.
Steve Unruh
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Iāve been thinking of utilizing at least a little bit of my heat for the Mazda. I plan to bolt down an aluminum toolbox for dry storage of wood and maybe routing along the length the first bit of cooling pipe before it becomes bed railing. Wouldnāt be super hot but might be enough to drive that much more moisture out or at least keep the wood dry.
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Ha! Ha! Here this is known as the husbands/boy-friends tune-up. Borrow her car. Go run the piss out of it for 45 minutes to an hour. Even on a gasoline vehicle this will burn off accumulated carbons and the forced high oil flow cleaning up of the valves and piston rings.
She will say thank you. (Just do not take her along for the procedure!)
S.U.
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Ha ha, my dad had a big Dodge station wagon with a 440 in it. Mom and him would put around town and it would start to have idling and driving problems. I would say to my dad can I take for a drive to check it out. He would hand me the keys and I would go out to the freeway 70 mph. And stick my foot in to the gas pedel. It would cough and sputter a little and then black carbon smoke would be rolling out the duel exhaust pipes. I would drive it for about 20 minutes and take it home and it would idle and run smoothly for a few months. Then I would do all over again. Oh I told my dad what I did. He thank me, he did not like driving fast. I had the station wagon doing 95 mph. Never got a ticket tuning my dadās dodge up.
Bob
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Just as I suspected āwwwwwaaaaahhhhhhhhhhhhhhtatatatatatatatatatatatatatatatata!ā
Carbon on the valves
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It is also strange Kristijan, I have tried several times to have charcoal on top of the wood, but notice no difference on the car, it was the same when I tried to run on wood with about 30% water, no noticeable difference.
If I remove the cone in my unit and put it in the bottom 5-10 cm above the grate, do you think it would work better then and go colder?
I have no need for it to go faster, but I wish it would be stronger on the slopes, and the ignition is difficult to change, I know, however, that Johan Hedenberg did it.
Iām so scared that itās going slowly uphill on the main roads, so I avoid them, as it works now.
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Jan, do you get much condensate in your sistem?
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It all depends on how wet the wood is, normally I can drive 5-6 hoppers and get about 4 liters from the hopper and the same amount from the radiator pipes.
With the wet wood, I have the same amount after 3-4 hoppers.
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Hi Jan, are you talking about the engine advancement for timing of the engine? If you are running on regular timing for gasoline, this is why you have no power. I need to have my engine advancement to about 38Ā° before top dead center for ignition. If I forget to advance my engine when driving on wood or change it back to normal timing on gasoline I lose power big time, no power to climb hills.
Get your timing changed to wood gas and I think you will be happy with how your gasifer has been performing.
Bob
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Jo and Jan and other friends , and this man said this:
Until Facebook, only your family knew you were stupid. (here I find myself too)
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I know, I know, but you do not have to say it so loud.
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Tone, I have no idea what youāre talking about 
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Yeah. Whatās a face book. Something with a lot of pictures of faces in it? I donāt know how to tweet either. I leave that to the birds.
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Do any of you understand if I can disassemble the brown black cord and change the ignition, and drive that way?
If I remember correctly when that wire is disconnected that removes the computers ability to advanced timing so you can set base timing of the distributor. So basically a timing lockout. But most of the 4.3 distributor have a square on the bottom of the housing with minimal adjustment with the hold down bolt and bracket. Not sure how far you will be able to turn up the timing. That has the cross fire flat distributor cap with the plugs wires on the side doesnāt it?
Yes it can be run that way thatās how shops use a computer to set the base timing. Though I have never driven one around like that, it usually checked at idle then lock the distributor down and plug it back in you can get some timing out of it but I think only a few degrees before the distributor cap will hit the intake manifold and the firewall and prevent any further adjustment. This will also change how the engine starts as the starter will be cranking against a ore ignition timing and will make the engine try to ābuckā the starter. I am lucky with my high torque mini starter I can leave my timing advanced and start it up no problem on gasoline or woodgas, most starters do not like cranking over an engine with 30+ degrees of timing
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Itās just like you say, my distributor is locked, I removed the lock before, but it can only be moved a little before it takes in the engine. ok may continue to drive as it is.
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