See “Mike’s venture into the dark side” topic for his water-cooled nozzle design.
Since copper’s thermal conductivity is more than 8 times that of steel, my favorite is still thick-walled copper.
I have an idea for building a durable and affordable flute-style (Kristijan) nozzle. My plan is to use a 1-1/2" schedule 80 pipe then lay a 1" round copper bar (or other long hunk of scrap copper) inside to “pump” heat from the nozzle to outside the reactor.
Hi Bruce, can you draw up a skech? Not quite picturing this in my head of what you are talking about. Thanks.
Bob
My concern with that plan is, there wont be enough contact beteen pipe and copper to transfer heat between them effectively. Also, the copper will be laying on the bottom, but the max heat is on the top.Then again, the sch 80 pipe has been proven to work on its own.
How much of the heat in the pipe might be radiant heat too? I think it should improve heat transfer. It’s an essy essy experiment anyways.
What about going the other way, are there pipe sizes where copper could clad a steel pipe?
Andy and Garry,
Thanks for helping me think about this. This morning some of my pieces of junk bumped into each other in my imagination. I have a tall military surplus ammunition can (30" X 6" X 11") that I’m thinking about using as a test reactor. I’m thinking of placing two 1-1/2" schedule 80 pipes parallel and five inches apart across the bottom and through both sides of the can. With a 1/2" hole in the middle top of each pipe and each one brazed where they pass through the can walls. This will give me multiple options for testing.
For a helpful update on charcoal nozzles see posts 255-260 in Toyota Corolla Vehicle Gasification Project. There Steve Bowman gives pictures and discusses the Leitinger nozzle with the inventer.
I welded five cooling fins to the nozzle to help cool the nozzle and preheat the inlet air
I can’t wait to test this new nozzle I will keep you posted as soon as possible 
Thierry
This is something I have not seen before, internal cool fins on a nozzle. Yes keep us informed on this. Maybe there is, something that has not been tried yet in the world of Gasification nozzles.
Bob
Hi Thierry , It will be very interesting to see how well your new design stands up , well done you for still giving this plenty of thought with the air cooling fins .
Good luck
Dave
I was thinking of injecting a jet of water vapor into the nozzle of my coal gasifier instead of a drip. has anyone ever experimented with calibrating a small nozzle to deliver an amount of water close to one to two drops per second ?
I imagined a water tank which feeds, by gravity, a small tank at constant level, in contact with a hot spot of the gasifier. by stabilizing the parameters (temperature, volume of heated water and pressure) it may be possible to stabilize a steam flow?
What do you think
Thierry
I like the idea. It could get a little difficult to regulate as temperature and pressure vary, and there’s a temperature lag with varying demand. If some kind of peristaltic pump could regulate the introduction of water in relation to demand it should work fairly well. Otherwise, a carburetor has been suggested to regulate water.
Why not try hooking up a nebulizer to deliver the water vapor? I find the drip to work very well as the liquid water turns to steam as it travels down the nozzle and is totally vaporized by the time it gets to the glowing charcoal. I have also found the amount of water you can add is affected by temperature and relative humidity. I remember well the day when it was just above freezing with lots of fog and a lot of water condensed out in the filter. This was with out a drip which showed me that there was more water in the air than the charcoal could split.
Gary in PA
Thanks Gary, here in the wet Seattle area I have had that issue.
My charcoal powered lawn mower has ran poorly and then I found 1/4 cup of water in the cyclone.
Last summer I never had that problem
THANKS Gary
I ignored the alternative of using a nebulizer to get water into a generator. Can we dose the fog flow of a nebulizer?
the main objective of injecting steam instead of water comes from the fact:
1: my nozzle is vertical and the water can therefore only rise there under the form of steam.
2: I did not find a way to build a precise and easily adjustable drip (how do you do it? )
Thierry
If you can get your hands on an Iv bag and tubing, that will get you a very precisely metered drip.
Had a slight accident while poking a bar up into the gasifier to clear some molten slag around the top of the nozzle , i must have bashed the bottom cool end of the nozzle and broke off a bit of it , i cleaned it all up and just replaced it back into the nozzle holder that luckily covers up the broken end . this nozzle is now 2 years old i think and is getting some heavy use again here during winter 3 or 4 hours run time at least 4 times a week .
This has certainly been the longest lasting nozzle of them all so far
I think i may have to buy a few more just in case i get heavy handed again .
Remind me, what material was this nozzle? And is it mounting in a cast refractory nozzle holder or something else? You certainly have gotten a lot of use out of your gasifier; it seems like a very robust design.
Dave, Did you ever get a chance to test the tungsten carbide sandblast nozzles? I can’t remember where we are with those. I have one in my ammo can gasifier that has not been fired up yet.
Dave & Brian,
That is the Thick Wall Hexoloy Silicon Carbide tube nozzle, isn’t it? I bought two of them after your earlier very positive durability report. I have mounted one of them but not used it yet. Glad to see it continues to hold up well–just have to be careful about banging against it.
Anyone try using ceramic clay? I just so happen to have a big block of white ceramic clay. Its for the battery tech Im playing with but plenty there for making nozzles. I would think the gasser would make a great kiln to cure it.
