Nozzles for Charcoal gasifiers, part 2

I have never used a vacuum gauge or manometer on any build or any engine , and have run engines from 50cc up to 500cc on what ever size nozzle happened to be in at the time and so have used from 10mm right up 25mm with no noticeable power drop or advantages , i always try and run whatever engine at full load , and if it wont do the job i move up to a larger engine .
Carl have you used a water drip yet to increase your power ?

Jeff i was just saying that most systems like mine will always have charcoal left on the outside of the walls as it funnels the charcoal down from the middle even yours will have charcoal on the outer wall on the fuel hopper and the main tank when empty unless its being shaken around
Dave

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Hi Dave, at this point we are splitting more hairs than firewood. :grinning:

All I am saying is that I feed the crater and try to keep the variables from varying. So instead of a V shape I strive for an inverted V shape that is constant. Me like constant. The top fuel hopper could have a cone shaped bottom. When it come to charcoal almost any design will work, the rest is our entertainment.

Solar-Fuel, onward !

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In reality the difference in power between my small nozzle and the larger one is really only about 20%, which seems like a bit, but might not be readily apparent if you werent hunting for the max output. Just sizing up to a bigger engine is probably the easiest route to meet a given demand.

This was the engineering approach that put the soviets in space before anyone else, and I will say that it has a certain logic. Perhaps the ‘refinements’ I am seeking will wind up a dead end, being more work or expense than the modest gains they produce. I have a tendency to try and push the limits, and make things more complex than they need to be. If I get to the point where I need to rely on a charcoal generator daily I will probably find myself building something closer to your Soyuz (does you big gasifier need a name, btw?).

I figure I might as well generate some data while I have everything set up, and so I will probably weld up the hole and re-drill it to some intermediate size just for the good of the order. That will give the next number-cruncher to come along a good starting point to improve upon :grinning:

Oh yeah, I have not really experimented much with water. I did squirt a few blasts into my nozzle at some point just to see what would happen and… nothing did. Engine didnt seem to even notice. I would like to play around with it though and try to be more scientific. Do I recall correctly that you can in theory burn as much water as charcoal on a mass-to-mass basis?

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Lol its ok Jeff i wasnt trying to be smart or rude i was just trying to understand why you quoted what i had said about the inverted funnel of charcoal , mine only becomes a problem after 4 hours run time but a smaller hopper like yours and Carl’s will get there a lot sooner is all , am i right in thinking you can refill your fuel hopper on the go so to speak ?

Dave

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Jeff, your system makes more and more sence to me and althugh its completely different to what l run now l am thinking of implementing some things to it based on the principals of your gasifier.

Carl, do give water some more experimenting time, you will not be disapointed. Yes in theory one pound of carbon can reduce one pound of water but thats with no heat losses. Realisticaly a lot less.
One important thing to note if you decide to give water more try, once you spray water in your gas will reachen and the air/fuel ratio needs to be adjusted (leaned).

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Carl and Dave,

This discussion has significant implications for me. I want to use a charcoal gasifier to power a 200cc cargo trike in Rwanda. I can’t increase the engine size and I need as much power as possible. So it sounds like I need to experiment with nozzle size and use water and make sure that I keep reaction temperature optimized. I’m assuming that we will need to use gasoline or hybrid power for climbing up out of our valley with a full load of products for market, then use the gasifier for the mostly downhill drive home.

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Bruce dont forget the gearing aspect. In your application I dont imagine speed is primary concern.
It makes me think of some of my old popular science magazines. Guys built what we would call garden tracors from junk. Thy would often use a 3 hp engine, but could pull car out of the ditch with it.

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Yes, Andy. This machine has 5 speeds forward, so pretty good low-end gearing.

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I put my 100lbs propane tank into a Harley servicar , the ones used by the traffic police/ parking officers . the engine was a old cast iron v twin that on petrol was so underpowered it was embarrassing at times when a steep hill came into sight but we still decided to see how it would run .
Well as expected it was a little hard to get going on a slight incline of the road , but once moving it sorta ran ok , it had a lovely whistle to it as it went past downhill , we decided that the gearing needed changing to be able to use charcoal on the road and thats as far as we went with it .
Brian had his mechanic change the gearing and try and tuning up the as best as he could .
Maybe when things cool down over here we might have another go now the gearing has been changed and see how much better it will take off from a standing start .
Dave

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By the way Bruce the nozzle size in the propane tank at the time was 1 inch , we may even try the 15mm tungsten nozzle and see if that makes a change too :grinning:

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The smaller diameter hole will increase the “velocity” of the air stream.
It’ll be like blowing on a campfire to get it going. It may be just what you
want/need.

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Dave, good question. I have thought about that but never the time to try it.

I didn’t take it the wrong way. Just tossed it out there. Some days I have less energy for typing/explaining so people might wonder what the heck is he trying to say. Other days, well, more energy. Just give me a poke and ask.

Solar-Fuel, onward !

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I decided to cut out the middle section of the inside of my insulated chimney pipe reactor. I left the bottom 12 inches to contain the reaction and the top 4 inches for rigidity and sealing.


I just snipped around the edge and folded over to hold the remaining insulation in place.

This should make the top of the reactor run cooler and it makes room or several more gallons of fuel.

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Thermal decomposition of water into hydrogen and oxygen takes place
at 2200 to 3000 degrees centigrade. Not going to happen in a gasifier.

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Pepe, plese search Water gas. In a gasifier, water does not thermaly decompose but react chemicaly with carbon.

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Ah, yes, I see your direction now, thank you. I enjoy your
posts always.
Pepe

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Hi Carl,

Sorry for the later reply, my hand is still hurting but my spirits are up and going…

My remarks, be it in some strange order:
1: your generator seems to be in a “bad” shape as it sounds strange to me that your voltage drops so easy. Does it have a functioning AVR or how is the voltage regulated ?
2: What is the real output measured , running on gasoline, from this set, increasing load untill it drops 5 Hz
3: is the rpm adjustable by setting screw ?
4: how is the governor reacting to the changing load ?
5: what is your charcoal like ? is the gas smokeless, blue flame ?
6: how is the slag from your gasifier ? sticking glassy mass or more crumbling ?

My old and still running generator for testing ( 5 years abuse now ) has a 7 Hp honda clone engine ( 212 cc ) and does not have a problem to run 1000 watts ( on charcoal gas ) with carb and even 1800 watts load without the carb, both on 3000 rpm / 50 Hz

Adjusting the air/gas mixture is quite essential, depending the engine temperature and ambient air …

Running on lower vacuum should be slightly better coz , if the mixture is well balanced, there should be entering more mixture in your engine.

My rule of thumb for small engines:
Only if the engine runs 100% perfect on gasoline and only then, it will “perform” on charcoal gas, otherwise it will run , but…

1: check fuel / grade / quality
2: engine and filters… The slightest filter fouling will give you “headaches” to find out why are those murphy’s popping up
3: airleaks… ( seen and experienced that a lot, certain when i had to do startup at a show… )
4: smell your fuel when you refill or refresh next day…

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koen, question, did you put a little advance of ignition in charcoal operation, and how you do it to make the adjustment on your honda engine clone.

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186/5000
I understand your suffering, at the age of 21, I cut my left thumb, and it was grfé, a success, but the first days after the operation, a great pain. good luck.

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Hi Francois,

Yes, my engines are advanced, half a key width, by using a 3 mm rod inserted instead of the key, preventing the slipping of the flywheel… using loctite same time…

The doctor gave me some picture from the inside of my hand…
and put 17 stitches to close it again

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