Hello John,
Because woodgas burns so much slower than gasoline you can get the best results if you advance your timing when on wood.
Woodgas at an idle could be advance maybe 30-40 degrees BTDC and still run smooth. At very high rpms you could run it very advanced (as soon as the intake valve closes).
With my ford truck I have to advance it with a pull /push cable (choke cable) .
On the Dakotas the computer will set the timing as high as it can but does not have the range to go as high as I would like. I also have a choke cable on the disrupter so I can advance and let the computer work in a higher range to fine tune.
My V-10 has NO distributor and may not be advancing as high as I would like, BUT at 2000 rpm I am running 75 mph. (Big slow running motor)
I am not pushing the dodge brand; I have mostly used fords all my life. I was not able to get a V-8 motor in a little truck except for the Dakota. I want to make sure I have ample power.
It will hit a hundred quick.
In the bigger work truck I also wanted the biggest motor I could find. It happens to be an 8L V-10 in a Ram.
I believe that if there are complaints about wood burning vehicle around the country holding up traffic they might be banded or frowned upon
I try to design to stay up with the traffic and not to be noticed. I live I a very small town and if you asked if any have ever seen a wood burning vehicle they would say no. Even the coffee shop that I frequent if asked, they would admit they had never seen any critter like that. (Maybe a half dozen that sit at the same table as I, but none have ever walked out and looked at it)
Only the local fuel stations have noticed that I haven’t been coming around much in the last several years.
today i put some more miles on the ford… about 40 today … wood consumption is down after insulation and lower rpms are much more stable stalling at lights doesn’t happen any more… which is a good thing! i tried all sorts of timing settings and ended up finding that about 12-13 before top dead center seems to be the best spot for my setup. … I wonder why? today i was plauged with wet wood … it is my own fault… i cut up some red oak i thought was seasoned for a year… i have since discovered it was just added to the pile so it was quite green … sigh … but even still i could get 50 mph once the truck was rolling … once i got some dryer wood in it she was much better. pick up is still sluggish and i suspect it will stay this way until i make some changes with my system… (larger restriction zone,larger restriction hole… i think a 3" hole is too small. angled nozzles (for bridging troubles) adding more pre heating of the intake air… etc etc…) I’m thinking of working with exhaust heat say a pipe inside a pipe under the truck? a 3" length with perhaps a 4" or 5" pipe welded onto it … then drawing the intake air through the cavity between the two pipes? from there running across my outlet gas pipe the same way as the outlet Gas can get to 1000 f. then into the intake on the barrel where the tubes feeding the nozzles will pre heat the intake air yet again …what do you think? other than that the only other improvement i see is adding another 2" line to carry more volume of gas to the engine…im not looking to win a race i just want to be able to climb a hill with the rest of the traffic … not at 20 mph… which seems to happen 50 % of the time … i do realize i had wet wood today though… so ill test again with dry. another idea i had today was to hang a 8 lb window weight inside the hopper on a chain attached to the lid. this would sway back and fourth when you are driving and maybe help the wood to fall and not bridge. just an idea i had. it could hang on a chain and be about 1 inch above the nozzle ring so it wouldn’t be hitting the nozzles. and since its on a chain it would be out of the way when filling … idk won’t know unless i try it.
Mike Briere came out to see my truck today and he had his gasifier with him it was nice to see the inside of another one since I’ve only seen pictures and my own … i can see room for a lot of improvements on my truck from looking his set up over! we took my ford for a drive and got to 45 with little trouble today . i understand he’s been out to your wood gas day. I’m sorry ill be missing that but I’ve got to work … it was nice to meet you Mike glad to know there is another wood gas guy near by. thats it for today have a great day all !
John, I am in the process of sizing and placing nozzles in my experimental Brandt design gasifier using the sizing charts from “theory of gasification 2.2”. I have a couple of questions about your double nozzle setup. You said in your post above on 3-18-12 “i think the two sets of nozzles really work well and ill do it again. this time with the ability to fine tune the different nozzle rings .” What is your feeling about the flame pattern by the ring of small nozzles; do you think there is enough velocity thru those small holes for the flame pattern to reach the center of the hearth and restriction? Why then did you add the 1/2" nozzles? Did you do any calculations for total nozzle area sizing? However you figured it, it must be close to right cause it seems to work well. Thanks!
Don M
my actual plan was to block off the fist set and use the second that i put in … the first set didn’t work to well … but i didn’t have a restriction zone then either … i added the restriction zone and second set of nozzles at the same time… i actually have not tried running on one set or the other and perhaps i should … i did however notice a bluer flame and more flame when i opened the first set with the second which is about 20 .200 holes. they are burned in with a torch so the size varies. you can see them in my earlier pictures… i didn’t do much math when i decided to do this and i feel that i need to increase my nozzle sizes and restriction plate size as well. but i have elected to do this when my current set up fails or melts… it hasn’t yet and the more i drive it the better i get at knowing how to run it better .just like wayne suggests 25 % machine 75 % operator. i have learned much more about this from actually doing it than stressing over the math and science behind it… bottom line is it works. just build it. ill try to post a pic of a nozzle diagram i sort of copied. this is from one of the fellows on the yahoo wood gas site i can’t remember who’s off the top of my head but i can not take credit for it… i found this after i built mine but its kind of similar.
Hi John
Nice Build! Gotta like success.
Stephen Abbadess is his name, Does he know ya used his design? If not I expect he would be happy to hear it. I Built a couple from his plan… Good clean strong gas. I made quite a few changes on the second one, mostly to do with pre-heat and conservation of heat. I’m thinkin Waynes influence would make it even better.
Good to watch you’re progress, appreciate ya sharing it!
TerryL
Hi JohnWells!
The Y.Woodgas fellow would have been Stephen Abaddesa (sp). Very interesting you have verified actual engine running capability on this 2 stage burning system along with TerryG? L? and ArvidO. I was quietly skeptical thinking it would be a cold center tar maker.
And THANK YOU!, THANK YOU!, THANK YOU! for verifing that common cheap woven fiberglass stove rope seal WILL air/gas seal if you just groove and clamp it tight enough. I argued for years now with some of the hard heads obviously never had a really good glass fronted modern air tight wood stove door sealed this way and then able to control and see the gasses change with the air controls.
Yep, yep more learned from from “stretch” operating any system fully before jumping in and gutting it out and “improving” it. Fella needs to at least put 5 full from a cold start burns - 10 hours before making any changes just to train himself. Another argument point I have now with some of the really good Fabbing guys seem more intersted in the building part than the prize of an engine producing useable shaft power. Gotta’ get the goo/tar/gas on you, engine sights sounds in your ears and the gas “in your blood” then you can make damn near anything work after a fashion.
Ha! Ha! Thats me now. Do not make sheeple proof systems - make systems to allow people to to express and stretch their abilities here out in the real world.
lol … im not sure it just seemed to make sense i works for my wood stove so why not a 55 gallon drum? and i wasn’t sure about the what changes i would be making so i wanted to be able to easily take the gasifier apart. i just found a rope seal that was big enough to fill the groove in the lid of the 55 gallon drum .(dig out the original rubber seal of course). then glued it in with high heat wood stove silicone . clamped it together and whalla ! it doesn’t leak and the system hardly ever gives a puff back. and I’ve taken it apart several times and just clamped it back when I’m done making changes … no leaks… i highly recommend trying it.
another 35 miles today … top speed 55 mph… wood consumption is down… the system ran for about 1.5 hours strait today and gas production got better after she got good and toasty… i was pulling hard on the gasifier tonight and the gas out put temp reached about 1250 f … i thought that was pretty hot! but the truck ran well maintaining 30-45 was not hard … hills still sluggish but i climbed them. the output pipe was glowing red ! geez! I defiantly need to resize this thing ! its only a matter of time till i melt it! (I’m planning on starting over from scratch on the next gasifier).
Can you hear it John? It’s saying “close off some of my nozzels!”
Maybe try to close off about a third of your 20 holes. If you are over oxidizing your gas you will have a bluer flame. But this is at the cost of burning a lot of useable gas also. If you can get the ratio right you will have more gas and cooler exit temps. This also means a denser and more powerfull charge going into your engine because the cooler will bring down the temprature even more.
You will want to test it first before putting it into your engine.
Good luck!
Terry
next time i fire it up ill shut down the entire lower ring … leaving just 5 … 1/2 " diameter nozzles and see what happens . I’ve gotten really busy at work and haven’t wanted to pull it apart if its working … last night was the hottest I’ve gotten this thing … too hot. i defiantly need to change those things… 5" restriction hole sounds good and fewer nozzles ilk you say … i have to wonder if the two stages make a better gas than one since i can maintain speeds around 50 with a 3.2 restriction hole? but one thing is for sure its going to melt if i don’t change something … oddly enough the reduction zone didn’t get much above 1500 F too much air = too much heat and too much burned usable gas in the gasifier? correct?.. ill run it again with just the top ring of nozzles and report back. only other thing was on start up i kept stalling the engine until i left the hopper lid open then it ran pretty well…once temps came up i closed the lid and it ran pretty normal.
Hi John that sounds a little HOT!! My 300cid runs 60 mph and the outlet temp runs around 600- 650 degrees, it would run around 750 pulling a load but then it would only go 50 - 55 mph. I am running a 5" restriction, and my nozzle restriction separation is only 5" but I wonder what would happen if I raised it one more inch. also We only have flat ground here so it makes traveling on wood easier though. Ron L
too much air = too much heat and too much burned usable gas …yes
oddly enough the reduction zone didn’t get much above 1500 F…this is normal…the reaction taking place uses heat so this area should remain at this temp…check your char and see if any of it is white, this would indicate oxygen leaking into in the lower part of the gasifier and can add heat. You have to determine if the oxygen is pulled though the grate or leaking into the gasifier from outside.
I pulled the char out this morning and their was a little white ash but it was only close to the 3" caps I use to light the system and the clean out cap.and the thermo couple probe… i keep thees caps loose so i can easily take them off . the char was black. once i got into it.
Any white ash that is concentrated anywhere in the bottom of a gasifier can be enough of a flare to rob you of engine fuel and raise the temp. This also causes the operator to throttle more wide open and pull harder which adds more oxygen below the grate especially in an undersized system further weakening the gas.
ok i hate to admit it but it works better with just one set of nozzles … i blocked off all of the lower set and run on just 5 half inch nozzles today wood consumption is down and more power output gas temp is down as well .and i made sure all the openings were sealed and as little air as possible was getting by there thermo couple. . seems i was burning too much gas in the gasifier before it could get to the motor… ok guys I’m ready for the “i told ya so”. lol i hit 60 mph today and 50 wasn’t to much trouble as long as i was on flat ground. hills i could keep 40 on … this is a huge improvement!.i tried to keep the engine vacuum around 30-40 and the gasifier was around 5-10 . total driving today about 35 miles. she ran well and never stalled.! is it possible to be able to maintain 50 mph on while climbing a hill once i resize the inside of the chamber? or is this the kind of performance i should expect? .
Don’t be silly John. I am so glad our advice paid off!
I would very careful about tar if you are burning chips, there is a lot of surface area there.
Again,I would think it would be a benefit to enlarge that restriction.
Terry
you know wayne keeps saying that the first sign is a sticky throttle plate … that hasn’t happened yet. but i do notice tar coming out the air intake… ewww… i can’t imagine what that stuff would do to my motor. today i burned chips … sometimes i burn chunks … chips are easier for me since they are processed already… I’m building a glass south facing half green house out of some old cold frames we had kicking around for the purpose of drying wood chips. ill spread a layer about 5-6 inches thick and let the sun cook them dry… it should reach temps around 120-140 inside i may put a squirrel cage blower to force air through the bed of chips … if its necessary. so far so good its 5’ wide and 12’ long should work well.
but I’ve got to work … it was nice to meet you Mike glad to know there is another wood gas guy near by. thats it for today have a great day all !
My 300cid runs 60 mph and the outlet temp runs around 600- 650 degrees, it would run around 750 pulling a load but then it would only go 50 - 55 mph. I am running a 5" restriction, and my nozzle restriction separation is only 5" but I wonder what would happen if I raised it one more inch. also We only have flat ground here so it makes traveling on wood easier though. Ron L