Caint seem too find what has been talked about on wood gasifier octain,are there any ruff estimates on the octain of wood gasifiers,? And or is there a way too measure octain,other than spark knock.
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I think wood gas has methane, carbon monoxide and hydrogen for fuel along with nitrogen and carbon dixoide. I don’t think there is any octane in wood gas.
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Its higher than gasoline i think, maybe its a dumb question with all the variables, though I thought there may have been a real ruff estimate,maybe not?
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You might be thinking of an octane rating which is supposed to indicate the fuel’s ability to perform like pure octane.
Octane is a very specific hydrocarbon C8H18 which is an ideal fuel for most internal combustion engines because of it’s ability to resist self detonation (knock). Most gasoline in the US is a mixture of Hexane, Octane, Nonane (kerosene), ethyl alcohol and a little toluene.
I don’t know what wood gas’ octane rating would be.
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No i dident know all the tech about octain,yes just about the compression ratio and or timing changes for some motors work better than others on wood gas, i know chris saenz said you can go up too 17 too one compression at max before spark knocking, so i then i wood suppose its over 100 octain maybe about?I think race motors run about 12 or 15 too one compression and use aviation fuel , 100 plus octain?
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Nobody’s actually rated woodgas for octane as far as I know. Generally it’s a very “high octane” fuel. Even though most people think that octane means high quality or high energy, that’s not true. It actually means a high resistance to detonation, which allows for higher compression ratios, allowing better performance. Woodgas has less energy but is very resistant to detonation. It can take 17:1 in a lab, maybe 14:1 in real life.
If you don’t have high compression, you can’t take advantage of higher octane… which is why we buy 87 at the pump. 91+ won’t help you unless your engine can make use of it.
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That answers the questian , Thanks chris saenz for the educated answer.That puts a spin on my octain factor.
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No idea if he’s right, but Ben Peterson claims it’s around 104 octane.
http://www.permies.com/t/42961/biogas/Wood-Gas#337232
In fact you shouldn’t cook inside with the gas because there is no smell added and there is some carbon monoxide in the gas. Its part of the fuel and balances the hydrogen giving an effective octane rating of about 104. Woodgas does well in high compression engines. Google “Mukunda Gasifier” for info on that.
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That is probbly as close of a gess as one could have,and then the temp at hot spot and moisture level in wood could raise the hydrogen a little higher.with high enough temps,might change octain a little.I am googling MUKUNDA Gasifier NOW
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Couldn’t remember where we were talking about compression ratios and fuels. I’ve been playing with engines since I was 15 year old. That means for 59 years and all that time I believed that high octane meant more power. This goes under teaching an old dog new tricks. According to an Engine Masters I just watched, and as Cris stated when this thread was started, octane is just a measure of an engines resistance to pre-- detonation. It has nothing to do with increasing power, or altering timing. Still not wanting to think about all the money I’ve wasted unnecessarily buying higher octane gas.
You can watch this episode on a free trial from Amazon. It’s a couple down in the episode list.
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