I think it’s mostly because the flow pulls the reaction upwards and since a vertical nozzle or a horizontal flute is below the heat and reaction it doesn’t burn away as fast. You still need either water drip or an exhaust gas return to keep the nozzle cool though.
That would be my empirical blue collar explanation but I don’t understand the science of it.
Thank you that makes sense to me, I think I’ve seen images of burnt out nozzles and the damage was asymmetric. Probably due to the draw being at right angles to the nozzle.
I’m going to use the exhaust gas for now as it seems a bit simpler but later I’m planning to change to a water drip I think.
Justin,
Also, the mass of metal around the holes is thought to spread the heat out and avoid damage to the nozzle. When I changed from the straight pipe nozzle to the flute design in the Corolla it made a world of difference. At last check the flute had not deteriorated at all. For almost the last year now, I have not used the exhaust gas for cooling, only the water drip. When I clean out the reactor in a month or so, we’ll see how the nozzle took the heat.
Hi Justin , welcome aboard , if i can just give you a few pointers as well ,and i will try not to confuse things any more than needs be .
Nozzle , go with the flute for now its the easiest quickest way , look for some thick walled pipe , forget using the galv pipe its not thick enough to last a long time but if its what you have then fine for a short while extend the pipe so its maybe 50mm past the center of the drum and cap it off.
Now from the air intake side of the pipe you want to drill 3 or 4 holes starting with the first one about 3 or 4 inches away and then the next one maybe space them 25mm apart , hole size is a guess depending on the size of your genny , but if you start with say 4 x 10mm holes you can always drill them out a little bigger afterwards if it needs more , search for the post on here "Nozzles for charcoal gasifiers part 2 "
Does your generator have a electric start ? if it does then once you have got your gasifier up to temp just connecting the gas pipe to the mixer and away it should go
if you do not have an electric start then i would recommend taking the pull start off and using a hand drill with a socket on a short extension bar is the easiest way to spin your motor up if you are using neat charcoal gas , or as you said before start it on petrol and open your air mixer valve wide open and then connect your charcoal gas pipe , straight away you will hear it slow down and run rough as it is now overly rich leave mixer wide open and listen to it start to smooth out that is the point when you need to slowly close down the air mix valve you will then hear the engine speed up just ever so small adjustments and you will suddenly slow down again and be on char gas fully .
I’m no expert and i am sure everyone’s builds run differently to others but one of the few things they all have in common are these things , air leaks no matter how small will make things a real pain trust me when you think your 100% sure there are no leaks i would bet you a pint there is .
The other thing is your fuel , that black gold you have made needs to be as nice a uniform size as poss and it will pay dividends by keep the temps down and feeding evenly , now as Cody mentioned he has a electric chipper to make his charcoal down to the right size , i also have a wood shredder/chipper that was driven by a 5hp engine . but even at tick over speed the amount of dust is awful you will not last long doing it at the speed these machines operate at , if you get one then do what i did and take the engine off and replace it will a 12/24 volt wheel chair motor , it has tonns of torque and can be run real slow and it will crunch up the charcoal lovely through a 25mm screen that comes with most shredders .
anyway good luck and if you need any help at all just give a holler out we have all been there
Dave
Thank you all for your input. I can see that it will be worth my while to change the nozzle now rather than later, apart from anything else it’s an easy job. I’ve found another longer piece of pipe I can use (quite good thick walled stuff) so when I’m next at the workshop I’m going to change to a flute nozzle design.
I’m also going to look out for a scrap wheelchair motor or something similar. Maybe a cement mixer?
Hoping to get back to it tomorrow.
I find my self thinking about it the whole time while I’m at work on other things! Am I falling in love with some old tubs and bits of pipe attached to an old gennie, with wheels that look like Noddy’s car?
(apologies to all those who didn’t have the “privilege” of watching Noddy and Big Ears as kids and so cant recognise the reference)
One way you could crush charcoal is to take a sturdy piece of expanded sheet metal grating, maybe 3/4" sized, diamond grate. Just build a box for it and stamp on the Charcoal and what falls below you can sift out the dust and bigger pieces to be re crushed.
Something like this, good and sturdy to hold your weight. I’d have used this but it keeps the critters out of the drain on my porch!
Hmmm, put some music on maybe? Though I’m not sure what the neighbours would think if they catch me black from head to toe from charcoal dust dancing in a box!
Hopefully it shouldn’t be too dusty. Might want to get a tall pair of rubber boots with a stiff sole just so you don’t mess up any good shoes you have.
Well it wouldn’t be difficult to set up and far better than the two bricks method so that’s another thing I’ll be keeping an eye out for.
Think I’m going to have to take up full time skip-diving!
Do they not have scrap-yards in the UK? You might be able to find it new at a metal supply store. It’s labelled Expanded Sheet in the US but Diamond Grate might be another term for it.
Yes there’s scrap yards, just not particularly close to me. However my list of items to look for is getting longer all the time so a visit to the scrapper will soon be well justified.
It’s like Christmas shopping for men!
I love going to the scrap yards and car lots here. Pre-existing shapes is what I make most stuff out of. Just wish I had more money for hoarding stuff I could use.
Where about’s in the UK are you Justin ? i once owned a Noddy car , it was a 1936 Shirley bodied 30Hp flat head 4 cylinder nearly blew my head off at the brake neck speed of 50mph down hill , yes it was an open top and red and had skinny wheels just like Noddys one !
Dave
Dave Ha ha I can imagine PC Plod chasing after you on his bicycle!
Sounds like a nice car though.
I live and work in Glenisla 40 mins north of Dundee.
Never got a chance to visit Noddy’s generator today unfortunately, too many other things cropped up like usual.
In fact it may be a couple of days before I get a chance to put any of your advice into practice as a load of new work has come in today. I suppose I shouldn’t complain though, apart from anything else you’d be within you rights to call me a whinging pom then!
Justin , You have no idea how many times i been called a whinging pom , Birmingham born and bred, 15 years now living Downunder , shame its costs so much to live here these days you would be scared to get your wallet out here ( that’s the Coatbridge half of me coming out ) .
I came across your other postings and it showed your set up and it looked like you have it attached to the frame of the generator , the only thing i would change before running for real is the filter bucket , if its plastic get rid and replace with tin , your gasifier drum will put out some heat down there and along with the hot gas will have that bucket soften to the point of melting , the next thing is do not bother with engine exhaust return , i say this because if you are going with the flute design a water drip is easier and better to control for engine boosting power and cooling you will see how as soon as the water drips land inside the tube they will flash to steam and get sucked in and up through your holes just aim for 1 drip per second and you wont be far off .
The only drawback with a flute nozzle will be lighting the gasifier , now with fresh charcoal and never run before it will start up in a second once the flame gets sucked up the holes , once you start using it like i do everyday you always shut down with charcoal left on top of the nozzle and so the next day you are trying to light old charcoal and after each lighting it will get harder and harder because of the old charcoal and the mountain of slag that will build up on top of the holes , the slag build up is what helps protect your flute nozzle to a degree so i used to allow it to build up a fair amount before cleaning off , but at this stage i wouldn’t worry too much just to get your feet wet will be so much fun you wont mind the set backs and they help you in the long run .
Again though try read the Nozzle for charcoal post on here as it will explain how Bruce Southerland drilled his holes at an angle to allow a cleaning rod to poke the holes out and you might even see other types of nozzles and there that also work well .
Dave
Right I’ve made a few changes since the last posts so I thought I’d give you an update and see if you can find any glaring omissions or obvious blunders in the new design.
There’s a flute type nozzle (I did try playing it before I fitted it and the sound was amazingly good so let’s hope it performs as well making gas!)
It’s not as thick walled as I thought but I’ll see how it goes anyway.
Anyway I also got one of Kristijan’s two way pumps as a back up and I’ve set the whole thing up so it should be pretty easy to convert back to petrol whenever I need to.
And the engine return is still on there but only because it was already done before I fitted the drip.
So getting closer to start-up now.
The last major problem is how to go from 1" flexible pipe to 3" bilge blower, though I think I have a flimsy, and probably temporary solution in the form of old plastic orange juice bottles! Suitably higgledy-piggledy for this forum?
Haha, yes, it’s perfect. I see you have already discovered the many uses of the red high-temp silicone caulk, so I think you will fit right in around here. The most important thing is to always seal those air leaks! Keep the design as simple as you can, and then really get after it with the caulk and duct tape if you suspect air is getting in somewhere 
You can always clean it up and make it look professional later.
I would suggest that the blower never be inline with the engine - have a way to shut off the plumbing going to the flare; as sealing up a fan is a real chore. A small leak leading to the flare is not a problem, but if its going to the engine it will cause problems. Also, put a cheap little PWM module on your fan so you can adjust the speed.
For sealing questionable joints, l sometimes put bicycle inner tire around the whole thing. Like a failed condom 
Its looking really good now Justin , as Carl suggested take the fan out of line , it will cause you problems later on , i use a small 12 volt mattress inflator fan only cost a few $$$ with a built in battery and the inlet outlet size is around 25mm or 1 inch in real money , and perfect for starting a charcoal gasifier .
cant wait to see some running video soon , Dave
