That stinks!
twenty characters
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This is where I read that the gas is ready before it leaves the firetub (Have the book in Swedish) why it is upside down I do not understand
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There are to many variables not shown in that experiment to be able to compare. They dont show all dimensions or what type and size of fuel they used.
My latest gasifier in my Mercedes had a tiny gasifier, just a oxidation zone and a restriction with a grate right in the restriction. It had some amazing power despite the gasifier was tiny. Up to 130kmh on highway But, l burned “rocket fuel” all the time! Charcoal does this… runing it on raw wood alone the gasifier was much weaker, half the power probably and allso made tar so l only tryed it once.
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Jan,
That version (SERI English Translation PDF) is available free from the DOW library.
http://www.driveonwood.com/library/gengas/
It is even right side up. I found the Swedish original PDF somewhere, maybe from you? 
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Sorry Jan, l promissed you something the other day.
This is a quick and easy way for you to get more power and better performance.
Take out the restriction cone and insert a thick ring of steel inside.
This is your current system
This is what you want to achive. Notice how much bigger the gasifier became?
Notice that upward flow of gas under the restriction l was talking about. Unless you get a eruption this gasifier is allmost impossible to overdraw/get to geater mode.
You can allso prevent eruptions by fixing a mesh here
I had a few gasifiers closely resembling this and it works fine. Only thing you might need to do is periodicly take out a few scoops of reduction char to extract out any crap that might acumulate in like rocks, nails, hevy ash…
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Kristijan; That is interesting because it is basically what I just tried. As I said before, it ran like a jack rabbit chased by briar-fox. My problem was I removed my nozzles and just had the holes in the fire tube much like a WK. After just a short time I could see flaking occuring around these nozzle holes similar to what some have seen in WK. I thought about adding heat sinks at each hole, like has been recommended for WK designs.
However, the engine in my truck went south. I have got it running again, but can’t put my finger on why it quit running. I want to get it running on wood again, but I have spent 20 year experimenting with various changes to my gasifiers and now I just want to install one that works as a daily driver.
Here are pictures of what I did, that seems much like what you are suggesting.
Drawing of most recent Embert build. (it made clinkers in the char)
The actual gasifier
Opps! Wrong picture;
This is the gasifier with the nozzle, reduction zone, and grate removed; (restriction is 10 in. below the nozzle ring)
Your sketches are good, but now some dimensions would be good. I’m thinking of putting my nozzles back in— 10 nozzles – what size orifice?
And what size restriction? What do you mean by “irruptions”?
Sorry Jan for stealing your thread. TomC
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Thanks for the help Kristijan.
This one, can I run it on wood only, or do I need to mix with coal?
How far should it be between the nozzles and the restriction?
Is it better without a roster, why?
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Only if I needed, to tighten the charbed and boost performance.
150% of firetube dia, if possible.
Not better, but one way to make the gasifier internals bigger. (Keeping the grate and just stop cleaning out under it, will give the same result. What I did on the Rabbit gasifier).
More charcoal =》More gas =》More power when needed.
There are downsides though.
A spread out charbed will cool down faster and warm up more slowly. The char will get hot enough to be useful pretty much by the time you already accelerated from a standstill to 80 km/h. Meanwhile you produce bad gas with a lot of unconverted steam and CO2 in it. In other words - longer hesitation.
Also, if pulling hard on the gasifier, more char than you would like to see sometimes escapes into the cyclone. But you know that already.
Sorry @KristijanL, for jumping in. Correct me if I’m wrong.
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What governs the dimensions between the nozzles and the restriction, and between the restriction and the bottom of the fire tube?
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Tom, you basicly made a WK, but withour any firetube cooling. It works the same but seffers. Kind of like grinding off cooling fins on a ir cooled engine cilinder.
Eruption is when you pull too hard on a grateless gasifier and insstead of hot gases evenly passing up trugh the bed of char (under the restriction) you get like a volcano eruption, a worm hole made that just spits out raw hot gas and char.
Its why l advice a mesh above the char like shown.
JO, l culd not say it better!
Jan, only correction to JOs instruction l have is do use lots of char in the first few hours for the sistem to settle in. Even run 100% slightly damp charcoal for the first run, you need the huge reduction zone to build correctly, if there is a cavity formed and damp charcoal falls deep its ok. If raw wood falls in you have a problem…
After that you gradualy go towards 100% wood.
This gasifier will allso alow you to burn biger fuel, l forgot to mention. Less work spliting.
Jan, its complex math. But it has so many variables it is in my opinion useless to build a gasifier straight to theoretical measurments.
Its like saying “a man can hand split one m3 of firewood a hour.” I have hand split a cord of wood in 25min before (blasted down beech ) and l had wood so tough and knoty lt wuld probably take a day to collect a cord. It depends. So many variables.
Nozzles are not all that important. What you have now will work. Restriction however is the hearth of it all. Absolitely make sure you can replace it! Just make a shelf on wich a thick iron ring can rest. Start with say 14cm, if power suits you stick with it. If it makes tar, go smaller. If power is still poor and gas is clean, go bigger. You can make experimental restriction discs out of thin steel and once you find the right dimension, forge one out of thick iron rod.
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What have I embarked on ???
Thank you JO and Kristijan.
How are you going to do Tom?
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You have embarked on a journey that will test your patience and persistence.
Test your ability to be flexible and reasonableness in your goals settings, and declaration of goals achievements.
Only challenging journeys are worth the doing of them.
Regards
Steve Unruh
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Was out on a trip yesterday afternoon, we went about 50-60 km.
I think the car went unevenly, and got a little weaker all the time, just like something would get tight.
We went at about 70km / h, almost all the time, at the end a little slower.
This is what the soot in the cyclone looks like now.
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Is it moist? Looks lumpy/granular. You must be running really cool if there is moisture already in the cyclone.
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Did not think much about it, but the soot was not very dry.
Had a thermometer lying on the pipe out of the cyclone, it never went over 100 degrees / C.
But doubt it showed right.
Found this today, I think I need to do fix this.
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Remember Grånäs Ivar? He said there are 3 major reasons for a gengas vehicle not running right: Leaks, leaks and leaks
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Jan, anything less thain a solid weld or a strong threaded fitting has always ended in disaster for me
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I have grown quite fond of using rubber fernco connectors and caps instead of threads but they can get expensive.
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