That 6.1-1 ratio is mass, not volume-an easy error that had me flapping a bit
http://www.bioenergylists.org/stovesdoc/Anderson/GasifierLAMNET.pdf
It's in this doc, and quite a few others inc the tlud handbook.
World's smallest and lightest fan forced TLUD stove.
- Thread starter Teepee
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That 6.1-1 ratio is mass, not volume-an easy error that had me flapping a bit
http://www.bioenergylists.org/stovesdoc/Anderson/GasifierLAMNET.pdf
It's in this doc, and quite a few others inc the tlud handbook.
I knocked up an excel spread sheet, for no of holes and what size
I bought a bunch of cheap resharpened cobalt drills on ebay so used their sizes on the pull downs, you can see the tables below listing them. Its a quick and easy way of working out size and number for primary and secondary air, you pick your drill sizes, fill in the 2 white boxes, and it works it all out
I bought a bunch of cheap resharpened cobalt drills on ebay so used their sizes on the pull downs, you can see the tables below listing them. Its a quick and easy way of working out size and number for primary and secondary air, you pick your drill sizes, fill in the 2 white boxes, and it works it all out
It's only very crude because I don't know how to calculate flow rate yet an is only for TLODs...3 more years of school and hopefully I'll be on my way haha
So I calculate the area of the cylinder of my fire box
Then I calculate the sum of the area of my outer air intakes all put together
Then I calculate the size of my jets all put together
The I calculate my venturies
Since I can't calculate my flow rate or take the venturi effect into account it's very crude
So I can find out my rough gas/air mixture mixed in the outer wall and then I know how much air roughly can be taken in by the flame cap which is also dependent on the size of the venturies,
Since I can't calculate this accurately I can only try various different designs and use the info provided from different designs to make more efficient and cleaner designs which I have been doing but a lot of it is very dependent on windscreen play.
So do you have any ideas on how I can calculate flow rate or improve my design methods?
Cheers,
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Fantasic work on the spreadsheet, it will save me tapping away on the calc, thank you.
For calculating flow rate Slammer, you will need some very expensive kit. I think you are doing all you can, and it sounds like you are doing really well, keep it up. Knowing the flow rate will answer some questions, but open others up.It will also not tell you how to improve your stoves, as much as building and using them.
I have spent a few years digesting all that I can about tlud's, but tlods are a different animal and I think you are close to cutting edge stuff with the pyrolytic stoves.
Re; windscreens-check the CFD story on bioenergy lists and see the massive difference pot skirts make to the transferred heat and their different effects and heat pathways, It will change the way you look at wood stoves.
For calculating flow rate Slammer, you will need some very expensive kit. I think you are doing all you can, and it sounds like you are doing really well, keep it up. Knowing the flow rate will answer some questions, but open others up.It will also not tell you how to improve your stoves, as much as building and using them.
I have spent a few years digesting all that I can about tlud's, but tlods are a different animal and I think you are close to cutting edge stuff with the pyrolytic stoves.
Re; windscreens-check the CFD story on bioenergy lists and see the massive difference pot skirts make to the transferred heat and their different effects and heat pathways, It will change the way you look at wood stoves.
Its excel 2003 so happy to send you a copy if you can use it, just mod the drill sizes to suit your own
I didn't mean to be cheeky, I saw it and my brain told me you had uploaded it.
A copy would be great. Ill pm you with my addy.
No worries happy to share, if you have any trouble with it, send me the raw data, and I'll sort it out.
Tlud Dims
Outer body: Made from a cut down section of the flask wall. Height=60mm, dia=68mm weight =8g
Top cap that the firebox sits in made from the bottom cap from the flask for a perfect flush fit. This has a 62 mm hole cut in it. weight=8g
Firebox: Made from the drinking cup- Dia=62mm, height=45mm weight=14g The cup has been carefully flared out to perpendicular, so it drops into the top cap and creates a seal, like the Spenton Woodgas stove.
Holes- Primary=12 x 2mm Secondary= 12 x 4.5 mm Giving a 5.06/1 ratio. All spaced evenly. Top holes 1mm down from lip
The firebox is lined with 1mm mica paper. The bottom is coated in 1mm fire cement. A 40mm square hole is cut in the side to take the fan cowling. The top of the square hole starts at the bottom of the top cap. his could be circular to be more compact and lighter.
The pot stand can be 2mm high which gives maximum heat, but can smoke more on start up.
The fan produces 7 cfm at 5v and weighs 14g. The 4cfm model doubles the boil time. The holes opposite the fan provide most air, and an improvent could be made by using different hole sizes at different points, relative to the air inlet.
Outer body: Made from a cut down section of the flask wall. Height=60mm, dia=68mm weight =8g
Top cap that the firebox sits in made from the bottom cap from the flask for a perfect flush fit. This has a 62 mm hole cut in it. weight=8g
Firebox: Made from the drinking cup- Dia=62mm, height=45mm weight=14g The cup has been carefully flared out to perpendicular, so it drops into the top cap and creates a seal, like the Spenton Woodgas stove.
Holes- Primary=12 x 2mm Secondary= 12 x 4.5 mm Giving a 5.06/1 ratio. All spaced evenly. Top holes 1mm down from lip
The firebox is lined with 1mm mica paper. The bottom is coated in 1mm fire cement. A 40mm square hole is cut in the side to take the fan cowling. The top of the square hole starts at the bottom of the top cap. his could be circular to be more compact and lighter.
The pot stand can be 2mm high which gives maximum heat, but can smoke more on start up.
The fan produces 7 cfm at 5v and weighs 14g. The 4cfm model doubles the boil time. The holes opposite the fan provide most air, and an improvent could be made by using different hole sizes at different points, relative to the air inlet.
This is all interesting stuff, and I must admit to knowing very little about these stoves, which I find to be far too fiddly to use outdoors myself.
As for the world's smallest, then I think you could do a lot better that that (leg pull coming up)
I think you should be aiming more for this size if you want your stoves to be the smallest!
Now, that is a small stove, and fully working too
As for the world's smallest, then I think you could do a lot better that that (leg pull coming up)
I think you should be aiming more for this size if you want your stoves to be the smallest!
Now, that is a small stove, and fully working too
If you check the heading it reads, worlds smallest and lightest fan forced stove.
Which it is, and I like the look of it.
Which it is, and I like the look of it.
Wheres the pot stand?This is all interesting stuff, and I must admit to knowing very little about these stoves, which I find to be far too fiddly to use outdoors myself.
As for the world's smallest, then I think you could do a lot better that that (leg pull coming up)
I think you should be aiming more for this size if you want your stoves to be the smallest!
Now, that is a small stove, and fully working too
No pot stand, no stove.
It would be a good challenge though-FWIW, I think its do-able.
Thanks Hugo
Hi teepee.
Not sure what the comment below means to be honest
"It would be a good challenge though-FWIW, I think its do-able. "
It does already have a pot stand made from chicken wire (as do most of the coke can stoves I produce), and as for do-able, it already works and with quite a nice flame for a stove this tiny
It was made as a fully working model, not a curiosity.
Hugo.
I already knew that thanks....which is why I put "(leg pull coming up)" in my post, as the stove in my picture is OBVIOUSLY NOT a forced air stove of any kind.
Oh well, maybe I need to make it EVEN MORE clear I am joking next time
Not sure what the comment below means to be honest
"It would be a good challenge though-FWIW, I think its do-able. "
It does already have a pot stand made from chicken wire (as do most of the coke can stoves I produce), and as for do-able, it already works and with quite a nice flame for a stove this tiny
It was made as a fully working model, not a curiosity.
Hugo.
I already knew that thanks....which is why I put "(leg pull coming up)" in my post, as the stove in my picture is OBVIOUSLY NOT a forced air stove of any kind.
Oh well, maybe I need to make it EVEN MORE clear I am joking next time
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Hi Ray.
I like the stove, it is tiny. That invisible chicken wire is pretty special too.
"It would be a good challenge though-FWIW, I think its do-able. " -
I meant that it would be a good challenge to try and make a functioning tlud stove as small as your alcohol stove, and I think its easily possible.
It would be about as useful as axe made from sponge cake, though- a definite curiosity.
I like the stove, it is tiny. That invisible chicken wire is pretty special too.
"It would be a good challenge though-FWIW, I think its do-able. " -
I meant that it would be a good challenge to try and make a functioning tlud stove as small as your alcohol stove, and I think its easily possible.
It would be about as useful as axe made from sponge cake, though- a definite curiosity.
I presume your talking like the stove Colin had at Lomond?
For pop cans I use a stanley blade either taped or screwed to a piece of wood which is the right height, then you just push the can against the edge and start turning the can, perfect cut every time, takes a few turns, the thicker lynx can may be doable that way, if it doesn't at least you'll have an accurate mark for your hacksaw.
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If you have a Dremel or similar, you can clamp it in wood vice and turn the can against the spinning cutting disc.
This probably goes without sayin; For safety reasons, make sure the can is empty- or you may be crushed shortly after by hoardes of swan diving women in bikinis.
Love it, best reply of the week.
BTW Pete I think I found those sought after flasks of yours, went for the 1L rather than the .5L model, didn't have a tape with me at the time. I have a few other things to do this weekend, but should hopefully have enough time to have a play making a clone of your TLUD.
I've laid it out in autocad to look at ways of incorporating a TEG to power the fan, pretty tight, the windshield may be the answer.
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Top work, Stephen.
I'm really looking forward to seeing the results of the cloning, and I suspect you are right with the teg.
With this stove run time, I think it will be impossible to harvest any meaningful power from the tlud body, but the windscreen is heated immediately by the lighter fluid on start up.
The flat teg could be incorporated easily into the top side of the fan cowling, allowing the cold side to be cooled by the incoming air. The hot side could be contacted by a heat conducting probe that is integral to the windscreen, maybe made from copper, or possibly alu. This could cause problems with hot primary air, so would need the air flow dividing in the fan cowling, this would not be too hard to do and would enable adjustabilty of the air flows too, if the divider was angle adjustable.
I hope this makes sense.
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