Trying smaller file size, showing EGR etc on the Motofier. (Larger photo file seems to be taking to long to “process”.
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And here’s my previous reply, which I guess I goofed up by adding too large of a photo file, perhaps. Can’t figure out how to delete that previous reply, or maybe it is not visible since still processing …
So, around here it is so humid you can almost cut the air with a knife! You are burning ambient air in the charcoal gasifier. That is going to yield some water vapor, and hopefully a little hydrogen. Admittedly, not much hydrogen. But that water vapor in the gasifier product passes on through to the next stage, the engine. Meanwhile, the engine is mixing humid air with this charcoal gas (with some amount of water vapor in it, from the humidity, as mentioned above). I wish it weren’t so, as not running my Motofier on gasoline after the long Mother Earth News run, ten years ago, or so, left me with rusted rings and a stuck piston, necessitating a major overhaul. (It ran so well that day that I decided I never would run it on gasoline, again. Big mistake, not flushing it.)
So, water vapor is in exhaust, here at least - no way around it. Certainly you would agree there is CO2 in the exhaust, as that is what happens when the CO is burned. CO2 is a gasifier fuel raw material, provided you have sufficient excess heat. Bottom line, exhaust contains some H2O and CO2, in this location.
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In your case, possibly. Google says at 30c the dew point of air is 50g/m3. 1m3 of air weighs 1.3kg so thats something like 4%? Not much, at best. But its something for sure. More thain most of us have. But in reality its above say 10% when we start some serious hydrogen production.
Yes, CO2 indeed. And it does feed the gasifier with “food”. Increases fuel efficiancy. But the poblem is, althugh CO has a rather high caloric value, its a slug when it comes to burning so its not realy efficiant in an engine. We want the hydrogen mixed in, wich has an extremely fast flame speed to eaven things out. Then the hydrogen unlocksthe potentisl of CO.
On the double flute. Yes, l proposed the idea and made the first prototype/proof of concept but l only ran that for a few hours as a test since l had a WK hearth ready for the build. The double flute has since served in the blacksmiths forge.
Others caught the idea and developed it further so its probably best if you ask them. Don has one and Bob also.
Perhaps just some findings. In any flute desigh, you want a flute thats about 2" in diameter with at least 8mm thick walls. Holes shud be at least 2-3" apart and not too big. Progresively smaller if you feed air from only one side. In a double flute conciguration the holes must point upwards a few degrees. I will let the rest to others
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Hello MartinP.,
This is one of the best statements of purpose that I’ve ever read here on the DOW.
Keep’em coming.
Ha! Ha! Farther down your instance that hot air humidity IS significant beyond just what the calculation numbers will say . . .
Most of the time a fellow just has to live year after year to really develop a gut-feel for these kinds of things.
You and I think we know the cold from our days of experiences. Nope. No even close to understanding like the upper Mid-West US guys or those central plains Canadians fellows. One winter in the last 20 I got enough, long enough frozen time to experience wet frozen firewood put directly onto Hot charcoal beds . . . . Wow.
Most think they could math’s stretch their understanding to living at a mile-High year around too.
Again a nope, nope. This effects all combustions, heating, heats transfers, and even materials drying. Freeze-drying is real and effective.
No, no. Not me either here. I’ve only ever been a days visitor to those conditions.
So, just smile and nod you head politely. Get on with your getting-on.
Regards
Steve unruh
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Hey Martin. I didn’t know what a motofier was so I googled it and your video came up.
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Thank you, Kristijan, I will reach out to those guys, as well!
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Good work, Tom, that’s me! Like a circus clown, going round and round the culdesac, trying to get out of 3rd. My youngest son shot this all on the spur of the moment, one take. Barking Bloodhound, included.
Kindof made up the name Motofier. No water drip, only EGR, but only because it was convenient to add the EGR, inconvenient to water drip this Simple Fire. Also a ceramic nozzle. EGR definitely makes a difference, on this build. Home grown butterfly valve with elliptical plate, for same.
I wish I’d had a Urals with a sidecar - that would have been more practical. But I already had this bike, and an aftermarket rear rack was available.
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Definitely the nicest looking, cleanest set up I’ve seen.
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Thank ya, Steve, good to converse with you! Yeah, I got off topic and into the weeds a bit, but I just wanted to make sure we all had a grasp of what was going on, not many absolutes, things are different in different places …
And as to my statement of purpose, I spent a lot of time tinkering, learning, staying up all night a Jim Mason party in Berkeley (was really fun), going fast with a girl named Bo (wait, that’s from the ill-fated but great series The FalI Guy - I really mean go fast with a guy named Mr. Wayne). Been a great ride, and I’m not ready to quit, have a lot to do yet.
Finally, I should append my “statement of purpose” and affirm that I believe the WK Gasifier is the best wood gasifier designed and built to date, for vehicular propulsion! I don’t believe a charcoal gasifier can generate that much power in an engine. Many thanks to Mr. Wayne and Chris, for that, and for this!
My only interest in finishing the LaRosafier is that I was impressed with Mike and what he could do with obtanium. I enjoyed his company. Yeah, he could be inappropriate at times (most of the time?), but we’re all human. RIP Mike La Rosa.
Now, back to my Pederick Plate build. BTW, I contacted the Australian Intellectual Property department, they looked hard for the 1930’s to early 40’s patent, said they couldn’t find it. Said it was probably destroyed. Really!?
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Probably lost in a fire. You’d be surprised how much that printed info gets lost.
The US military lost a lot of veteran records in a fire a few years ago. Even in a FOIA request they can’t track it down.
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Oh wow thats you! I knew that bike looked familiar! Your video inspired me when l built my charcoal powered moped. And that project sent me on the trip of developing better charcoal gasifiers so all l can say is thank you!
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hello martin, your motorcycle is marvellous, we found it in a old thread of the forum…very nice build, -artistic and light weight construction…we took it in our collection of Motorcycles with gasifiers - #86 by giorgio
…one thought to the pederick gasifier…in the handbook is written that the gasifier always needs water drops -steam - for cooling, otherwise the fire plate gets destroyed…
this can be a problem when the charcoal has just much umidity by itself…
so a solution could be to make the fireplate hollow, , in way that water cooling can circulate in the plate and water drops can given only when needed …water cooling can be connected with the cooler system of the motor…
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Thanks for the kind words, @KristijanL and @giorgio ! Cool to think the Motofier was some kind of inspiration for more good work! And of course, many inspired me, before I built it.
Good thoughts as to “over watering” considerations on the Pederick - will have to watch that. Having a hard time conjuring up how large to make the hole in the plate, but will figure something out. Maybe it’s like the @don_mannes and @Jeff “bottom suckers”, just cut a plenty large hole and let it suck what it wants? Or, is velocity still important to create the gas quality, as per the Kaupp et al work?
I read in Charcoal Nozzles, 2 where @Jeff said he made a Pederick knock-off with a thin plate but with cooling fins. Wonder what his hole size determination was? (however, he normally gasifies smaller engines)
Have some 1" plate to use. Going to weld that to some HD square tubing I have, to contain some amount of water level. I wonder if they started off with some water in the plate area, prior to running? Need to look at the manual, again.
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I’m sure they turned the water drip on right when they were going to light. That heavy plate will take a few minutes to get to scalding hot temps so I think it would build a reserve of water. I’d start with a benchmark 1 drip per second.
Also it might be a good idea to start with a smaller hole, you can always make the hole bigger. Maybe use a step drill, so it will give the hole a Venturi effect and push the reaction closer to the center of the gasifier.
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Found the error in my above calculations! Was using an online calculator for IN2 to M2 (duh, divide by 39.37 twice) and must have hit a wrong button or something - the area for the 1.25" nozzle should be 0.000794 M2, yielding 36.5 M/second, close! Tried 1.5" ID, yielded 0.00114 M2 area, yielding … 25 M/second, which I believe is what several have suggested as an optimum velocity. Will have to take a look at the Kaupp reference, one more time.
Thanks @ForbiddenTuna for the suggestion for initial water rate. I don’t have a good step drill and that’s a lot of drilling on 1" plate. So, going to use the “step torch”, aka gas hatchet. My kerf will be irregular, but who will care?
Wonder if @gasman is still around on DOW?
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You could always hog it out with the torch and weld in pipe.
I think stepping down to make it more of a “jet” will help.
Make your true intended size using the pipe insert and leave a little step before it a bit larger diameter.
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Also, here Edmundo Ramos has made a decent formula for considering an updraft nozzle size.
It’s a direct link to the PDF of the English manual.
Edit: it’s on Page 7
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I can do a little bit better than “hog”, with a torch. First learned to use a torch in college, summer job … 45 years ago, at Hughes Tool Company. We were cutting off the 4 in plus thick legs of 26 inch, experimental drill bits. It was anachronistic at that time, even, but the local welding shop had a “special” for UT students, so I bought a Victor SuperRange set.
Great on the Ramos pdf, been looking for things like this.
Meanwhile, I think my calculations above are “gas” (to engine) calcs, as per Max’s formula, versus air to nozzle. Air looks like it is about 3/4 of the final gas flow. And gas composition results are in terms of air blast velocity. Diminishing returns above a certain point. I’m going to graph these and post them for all. Not trying to over-engineer it, but with datapoints like these, may as well learn from them.
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It’s a figure of speech.
Anyways, it would be neat to see a comparison between the different formulas and see what each recommend for your engine.
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Belated thank you, @tcholton717 !
OK, @ForbiddenTuna here you go, here is a comparison of charcoal gasifier nozzle sizing methods. Sorry it took a little while. But you know what they say, ask an engineer what time it is, and he will tell you how to mine the iron ore for the watch hands, and go from there. No, actually this analysis “needed doing”, and hopefully will be helpful to many. Really needs to be a PDF in the Library, or something, once it gets some review and comments. @k_vanlooken 's spreadsheet basically came up with the same answer as my laborious calcs based on Kaupp/Goss and work by @gasman - but then I don’t know that I used the spreadsheet correctly.
See the .PDF, posted a few replies, below …
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