Thanks Mike, before the “cookie spliter” I was getting tired of spliting with hatchet and my chunks were getting bigger as time went on. I didn’t really notice it and the Caddy ran ok but not like it did at first. Now with the cookie spliter I can easily make smaller chunks and will be from now on.That’s another lesson learned.
I like the “passing gas” info. That goes to show you guys that have been doing this for a long time have tried it all. That is valuable info for us guys that are learning, same with sometimes stalling after 200 ft., and the rod and tape strips, it’s all great stuff.
And Steve your info about the guys filtration system, analyzing w/o instrumentation, characteristics of SS. All that is good stuff to me and many others (even if they don’t want to admitt it.) Thanks, Herb
Hello Herb,
Yes, smaller blocks are like a very rich diet but don’t over do it. A very rich diet and light work might cause constipation . On the other hand large wood is like fiber . They will free up the system but may not be able to work as hard .
With a little more driving you will be able to tell what the gasifier is needing ( meat or greens )
BBB
:o)
The fish didn’t bite today … I think some of our local lakes are near dead… I’ll let the FIBs have them … I’ll stick closer to home now
http://www.intergate.com/~mlarosa/images/woodgas/blackhawk-lake-JM.jpg
Heck that picture is from 5 years ago … crap … But that is where I fish near here at the dam of Blackhawk Lake … I’ve driven there many many times on wood but stopped taking pictures a couple of years ago … M
Looks like a great place to go fishing Mike. Back to the fuel wood size thing, I suppose it’s because when we run smaller size pieces there are more sq ins of surface area giving off gas? Is that right? Herb
Herb, I used to fish in the lake but I can’t walk over the dam right now. I’m fishing below the dam in that creek. I can park right next to the creek and take my chair out of the truck and relax and have everything I need right there. Last time I was there (last weekend) the blue gills hit non stop. I brought 15 home but they were somewhat small but tasted great. We had 2 good meals out of them. Back to wood, just like bluegills, the smaller pieces provide more energy. I never go larger than the restriction diameter and I rarely run chips. Chips tend to glue together and then restrict flow and then plug the works or this has been my experience. I have found that every 3 or 4 inches in the hopper you can throw in a small layer of chips and then go chunks and then chips and it works very well. Somewhere along the way someone said optimum size was 1/7 the nozzle circle. Wayne’s design is a bit different than the standard imbert setup so a lot of these rules break down. I am running a 9" circle right now but can run up to 3 inch chunks just fine. I have run the smaller ones and get too much gas :o) … Also too much heat … ML
My burn tube and nozzle circle is 12", so 1/7th of that is 1.71 ins.
Does that mean 1&3/4" by same by same would be about the best size wood/fuel for my unit for overall performance?
If a person could make any shape wood/fuel there is, what is considered to be the best shape? Thanks for sharing the knowledge, Herb
Herb: Your system is a WK at heart, correct? If so, what Mike L. said at the end, “Wayne’s design is a bit different than the standard imbert setup so a lot of these rules break down.” would apply to your system as well.
Wayne told me that he thinks the optimal is just smaller than 1/4 of the firetube diameter, cubed, so 3" for a 12" firetube. My 8" tube should run 2" cubes by that logic.
Yes that’s right Brian, My burn tube is 12" with a 7" restriction, so 3"X3"X3" square blocks would make the best size fuel. Do some of you other guys agree with that? thanks Brian. Latter, Herb
Hey guys thst 1/7th “particle” sizing information was from Dutch John on his Microgasifers for high veleosity, small interal zones volumns (Imbert derivative) microgasifers using chipped screened woodfuels. He was using a willow type fuelwood I think.
S.U.
Thanks for the clarification Steve, sounds like if I shot for 2&1/2" cubes I’ll be pretty close.
I made a new steel frame for the cookie spliter so the chunks can go straight out the back and drop off stump into hotbox. With the old wood frame 2’’ behind hatchet head it was awkward getting that chunk out to get more cookie in to split, not anymore! It eats cookies like Pac Man eats dots! Still working on video. latter, herb
Hey Mike L, when you wrote “get 200 ft. out and may almost stall” what do you think causes that? I know mine does that sometimes, acts like weak gas or to much combustion air, maybe bridging a little. What do you think? thanks, herb
Getting in a load of logs tomorrow and I picked up a new bandsaw blade so I’m looking forward to “workin’ up” some fuel. Driving the Caddy to Council Grove Kansas next week, it’s about 350 miles south west of here, be there for about a week, latter,herb.
Mine does it too Herb. If it sits for more then 5 minutes. Somewhere between 100’ & 100 yds. I keep my hand on the petroleum PWM and watch the AFR. Most times I can “overcome”
Hey Herb,
Just curious - does the blade of your hatchet head drop all the way down onto the stump, or does it have a stop that prevents it from doing so? Seems like a stop might be useful for finger safety as well as stump durability. Shouldn’t have to go all the way through your cookies in order to split them. I know my chopping blocks start to come apart after a few hundred blows from a 10# maul.
Hi Herb and Carl
My system does a similar thing, I dont have 200 yards, I start the gasifier at an idle for a while, get every thing warmed up then rev it up to 50-53Hz then switch over from mains to generator, then she dies for no apparent reason! I have found that as she starts to die under load if I close the air a little she will catch and be ok form then on.
My assumption on this is the fire tube is producing gas for a low load then a high load is quickly put on to it, the fire in the tube is not great enough to accommodate the load so with the inrush of air you form CO2 and not CO and H, after a minute it all gets in to equilibrium. I think Wayne calls this the turn down ratio. Where your oxygen lobe reaches to far down in to your char bed!
Wayne please me correct if Im wrong ?
Thanks
Patrick
Patrick: From what I’ve read, “Turn Down Ratio” (TDR) is the range at which a gasifier will produce usable gas. It sounds like your idle pull might be below the low end of your gasifier’s TDR.
Wayne has said that once his gasifer is well stoked, say from driving his truck around for a while, that his TDR is much wider. This is because the system is hot enough in the core to produce the larger amounts of gas needed for a larger engine under load but has built up enough of a heat reserve to allow a lower draw of small engine or extended idle of larger engine.
You might want to try to run your blowers for longer at startup or slowly dail up your engines/generator load to get the gasifier hotter throughout the core before switching to a more variable load of the generators running your house/shop power needs themselves.
Hey Alex and everyone, the shaft has a dead stop, it stops about 1" from stump, I thought it would be a little bit less dangerous that way!
As far as the stalling I don’t know but with mine it seems like a fresh air control problem. herb
Added latter same day
Hey Carl, what does it take to “overcome” most of the time?
Patrick, “right on” good explaination of TDR
Back to that problem of stalling, I know my fresh air control works open on it’s own as I drive a little bit. Next thing I know I’ll let off the peddle and then step down again it may die. I push air control in again and starts right up. That scinio doesn’t always hold true but I’ld say more times then not. latter,herb
I “overcome” with gasoline, about a minute of 10-20% and off we go.
Good Morning Herb,Carl ,Patrick and all,
There are times you may notice a little lose of power even with the gasifier up to normal operating temp.
Example .
From a cruising speed stopping at a long traffic light then accelerating out. At about 100-200 hundred yards there might be a little weakness in power for four or five seconds but recovers with ample power.
Here is my guess what may be happening. At cruising speed the depth of char in the burn tube is kept hot but as you coast into a stop and wait for the light to go green the bottom portion of the char bed will go dormant . With the vehicle slow idling there is enough air draw to keep the char hot up near the nozzles but no oxygen left for the remainder of the burn tube. When the vehicle is accelerated from the stop it may take twice the throttle as cruise speed . There is enough potent gas in the storage ( filters ,piping ,condensate tanks ) to rev the motor drawing hard on the gasifier . The blast of air now hits the dormant char and will react quick but not instantly . Enough air gets through the dormant char before it comes back to life that it may be consuming it’s own gas ( heater mode ) for four or five seconds. This dead gas will mix and dilute the gas in the storage system and may be noticed 100-200 yards from acceleration.
Dormant char can react quickly but not instant , you can watch a blacksmith forge and notice the time the char takes from being dormant to live after the air blast hits it.
One easy way to avoid this little lull in power is to power brake just a little before the green light or do as Carl suggest and add just a little dino if needed.
I have also noticed when this little lull happens if I restrict the mixing air will usually help . This implies the composition of the gas has changed for a few seconds.
The above has never been a problem but just something you might notice. .
Good Morning
Sounds like exactly what happens in an actual mechanical gasoline carburetor. It those sudden demand trottle plate snap openings your intake manifold vacumn drops - less air flow then which in them as actual liquid fuel “suckers” sucking less airflow through you will suck in less fuel. The Air is lighter/less mass so airflow catches up quicker than the heavier/mass denser gasoline flow. Those of you paid attention carb rebuilding/tuning or had a carburetor accelerator pump failure know well in liquid gasoline carburetors this is masked over with that fast foot/throttle plate snap opening mechanically linked to an accelerator pump squirt shot of raw liquid gasoline. Yeah feather footed accelerating helps as keeping that intake manifold vacumn higher for better engine sucked in flows. PITA on an manual transmissions and in the modern 4 and 6 way intersections Internet High Speed living world of today - really pisses off other drivers.
I can see where manual closing down the air side mixing valve would help flow draw through the gasifier hearth - still be a fuel gas making and delivery delay though.
Those with gasifier primary air in booster blowers couldn’t you just flip on that blower to force air IN just before your anticipated accelleration? Be no real flow to speek of untill the snap open engine throttle let it flow through - you’d mostly just be building up a little pressure to assist flow through the hearth core once the engine trottle plate is snapped open. If this works you could put a timed “stab” switch into that booster blower circut.
Regards
Steve Unruh
Herb
How far west is Council Grove from Olathe time wise? Been working in Spring Hill for the last month which is why my build has been at a dead stop.If I can break free would like to see a real life touchy feely run down the road gasser. Especially a uneat one as yours
Tom