Hi Jo, I would only add insulation around the hot zone in your place, with aluminum sheet on top, so the infrared radiation is reflected inwards, the heart temperature would rise, the gas would improve a bit and when the vehicle stops the middle does not cool down so quickly , so I would probably have a better acceleration, the only downside is that when I park the vehicle, the gas would come out for quite some time without fresh air, but you probably already know all this and do not resent when I act smart
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That “skizz” helps a lot. The dead gas area space coming out of the bottom of the gasifer and grate area is bigger then I originally thought. My drop box area is filled with the heat exchanger container with fins on the out side this collects soot and causes turbulence with the gases velocities not dead gas space. On yours the fins are kept clean and transfer heat more efficiently back to the incoming air. A Big improvement right there. A large open area for fine soot to drop out befor going out the very top, and ash/soot to settle down in the bottom. I see completely dead area in the corner to collect ash/soot /charcoal . Below the grate area is more ash/charcoal settling area, and when empty becomes more area for gas reserves. Great new design on the WK Gasifier consept. Thanks JO.
Also thank you Tom, for many good questions that I didn’t think about to ask JO.
JO did you ever do a final weigh-in on the gasifer and parts add to the Volvo?
Bob
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Tone, this is how it’s already insulated. Rockwool on the outside, natural ash cone on the inside and the heatshields somewhat spaced from the firetube.
Unfortunately I didn’t, but I was able to lift the gasifier in and out of the trunk with some effort. My guesstimate is around 100 pounds + cooler/piping.
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JO,
Why do you have a spring loaded tennis ball on the intake air??? Nice skizz. Saves a lot if typing TomC
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To allow one more thought, Mr. Wayne mentioned a massive restriction plate to increase inertia, even an upright massive tube adds mass and at the same time lengthens the glowing zone because it is not cooled by the intake air.
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Tom,
I was about to say: - Don’t we all? 
I consider the tennisball shut-off valve to be one of Wayne’s signature inventions most of us adopted.
I must have produced a pretty good drawing if all your typing condenced down to one single question?
So, I’ll add some additional FREE information.
As you can see there’s no cyclone on this build. However the inner vessel on the heat exchanger has “auger-fins” on the outside - in the air-path - to create a swirl and give off heat to the incoming air. Also, it has vertical fins on the inside - in the gas path. I welded them on the day before Wayne mentioned, in another thread, that he stopped using them due to ash buildup 
But I haven’t discovered much buildup yet, so I guess I’m ok.
Also, the “crossover” has fins, length-wise in the gas-path and “cross-wise” in the air-path. The two-dimetional picture doesn’t give justice to the surface area involved.
Tone, that’s true, but with my driving habits I will rarely have time to fully heat it up.
However, I plan to add a beefier restriction and even raise it an inch or two. That will add to the insulating ash cone as well. Because of the low temps I see I’m pretty sure I will have enough depth to the charbed anyway.
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I used a car brake disc and welded holes from the screws, some are air cooled and very massive.
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Good day Jo , have you done any measurements of wood consumption per 100km , Jacob says something like 1 kg per mile , Joni says 14 kg/100km , I would also be interested in Jan’s consumption . I know I’m annoying , … well, here is some literature for those long dark evenings.
6) review on gasifier modification for tar reduction in biomass gasification_adi.pdf (592,0 KB)
[email protected] (578,7 KB)
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Good morning Tone .
With my v8 dakota driving flat land with speeds around 50- 60 mph I will usually get over a mile per pound. 1.25 miles in most cases.
Test at Auburn university showed 231 miles per million btus of wood .
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Good evening Tone.
No worries. A slight annoying feeling only occurs when “city-people” tell me things like how I would be able add automatic lightup and refuling. However, watching Wayne’s pic from the other day showing Lisa fueling up, gave me an idea 
Three different gasifiers/vehicles and the consumptions look something like this.
Rabbit : Volvo : Mazda
2.0 : 1.5 : 1.2 mpp
13 : 20 : 25 kg/100km
These are rough numbers, but the differances pretty much represent what to expect running petrol. Weight and size of the vehicle are the most imortant factors. Gasifier and engine - not so much.
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My B2000 got 2 miles per pound on charcoal, I can’t wait to see how it will do on raw wood.
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I apologize to Jakob for writing 1kg / mile, the real figure is a pound / mile, similarly stated by Mr. Wayne, in both cases the figure is the same, namely 20kg / 100km, I also apologize to Joni, who got 12kg / 100km in the latest version. Jo, you probably have a decimal point too much in the data.
If we know that the wood has somewhere 4kW / kg, at a consumption of 20kg / 100km, it means that a larger vehicle on wood consumes wood energy of 80kW / 100km.
Let me translate this into gasoline consumption, that would mean somewhere around 9 liters / 100km. Interesting, interesting, such a car with driving on gasoline certainly consumes more, at least 12 liters / 100km.
How would you explain this, if we take that we lose at least 25% in the gasifier, we get ideally 3kW from 1kg of wood in the engine, so in fact the engine drives only 60kW / 100km, and when driving on gasoline 105kw / 100km.
Summary of thinking:
a wood-powered engine has 40% better efficiency than if it consumes petrol under these operating conditions. 
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Cody, remember the numbers show long distance non-stop driving. Short distances, shutdowns and lightups can sometimes make you consume twice the amount of wood.
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My math for the B2000 was based on a 26 mile round trip I did, measured how much was used up and using gallons weighed out my charcoal. At the time my charcoal was 9lb per 5 gallons.
I’m sure on longer drives it would have been even more efficient. I would have to go about 2 hours east to find flat ground though 
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Correct 
I corrected it. Thank you.
We usually tell consumption in 10 km up here, that’s why my error. 10km is a Swedish mile (mil). We save on zeros that way 
Wood is 37% more efficiant in an engine. (Auburn university, Alabama)
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I don’t understand English well, but I haven’t been given an explanation of where such a difference arises, but to sum up my thoughts:
Because we know that on wood gas, the engine develops 25-30% less power, so the cylinder must suck almost always close to 100% gas, which means that it operates at high efficiency, unlike if it runs on gasoline, for the same power the cylinder fills with a much less combustible mixture and moves down the efficiency curve. I am attaching my sketch for reflection and critique.
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Tone, I think it has to do with how much is wasted as heat during combustion. A diesel for example, is more efficient than a gasoline engine. Diesels sold up here have an extra cab heater (diesel fueled 
) , because the wasted heat from the motor is not enough to keep the coolant warm enough.
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Tone the difference is in the up and down piston; connecting rod to crankshaft power conversion device.
The compressed air&woodgas ignited burning is able to apply pressure effectively over more degrees of crankshaft rotation.
Gasoline is too much a boom-boom fuel in IC engines cylinders.
Woodgas a woosh-woosh IC engine fuel.
Proper IC engine engineering: look up the BMEP graphs. That is what to follow. Not fuel BTU’s or heat joules.
S.U.
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I hope this translates for you.
Even this is too overly simplified. No accounting for crankshaft angles. Time of effective angles versus combustion speeds. ect. ect.
IC engines it is easiest to just measure results.
S.U.
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https://youtu.be/t9UI8Qv1xcA
I just love this video of JO making a batch of rocket fuel mix in his hopper. When I do the exact same thing there is a big difference in the performance of my truck.
Like @KristijanL has said it helps with the extra moisture in the hopper, by the dry charcoal absorbing the moisture up like little sponges. And then going through the fire tube to make more Hydrogen H2 with Carbon monoxide CO and Methane CH4 gases. It is a plus plus, Win Win.
I always screen my biochar down to 1/4" or larger. The smaller stuff can be used in a charcoal gasifer with out the ash 1/8" to minus 1/4" . The ash and what is left over from screening goes into the garden.
Bob
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