Questions about Rocket Mass Heater self contained.

Hi everyone

Im new to this forum, posted a similar post yesterday but i have made development today on my project.

I went about seeing if i could create a miniature working model of this burner i want to make, anyway i will cut straight to it, it didnt work. However this has not phased me and i am still going to continue onto the larger version, i do however have a couple of questions for anyone out there who has made any type of Rocket mass heater. (i have also added a couple of photos of my model as i think it looks pretty cool.

Will this model, scaled up actually work?
has anybody done this before?
what sorts of temperature do you get out of these rocket mass heaters?
how could i make it better?

ok so this model, the green tube is insulation for the inner tube (in the large version this will be an outer tube filled with insulation for the inner tube, its made out of copper pipe and 2 tin cans.

i could get a good suction going and it would burn outside of the tube and suck all of the flame in so there was a powerful suction there, but i think that is the problem, with it being such small scale it could not handle this amount of air rushing through and it just blew the flame out, also i do not think that there was enough space to burn anything there (maybe if if i double the size of the copper piping i would get it to burn but to be honest i'm not that bothered about a mini version of a rocket stove)

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Thanks for looking and any feedback is greatly appreciated

Josh

it will kinda work. to much draw with that long of heat riser in proportion to the rest of the system. However those little systems can teach you lots.
A few other problems like the all metal construction lack of mixing in the burn tunnel Etc.

Ahh ok so would the system work better if i reduced the length of the pipe? im going to build a brick one this weekend and search for some oil drums and ducting! hopefully i can source the materials for free and that way i am not loosing out if i do something wrong.

the system will burn cleaner. cardinal rule for wood burning. time, temperature, turbulence. how long the fuel is in the heat, how high the heat is, how well mixed the air and fuel is.

we dont actually burn wood we burn the gases produced when wood is subjected to heat. those gases need mixing in order to burn completely (burn tunnel is to smooth) the gases need time in the heat to finish the burn (to long of heat riser) the wood needs heat maintained in order to oxidize as far as possible. (no insulation around the feed tube and burn tunnel)

i like this little thing, im curious if youve done anymore with it as a small, near handheld system may work well in a small camper or something to help keep things toasty in the winter

While I do like the rocket stove, I'm wondering if any have tried to build a kachelofen by its German name, sometimes also known as a Russian Stove.

My mothers home had one very similar to that shown at the top of the following Wikipedia page http://en.wikipedia.org/wiki/Masonry_heater

Essentially these are tall units in which the fire burns near the bottom then the smoke rises, does a 180 turn, comes down a channel then turns 180 and rises again to gather at the top and be expelled out the chimney. The are available commercially, but can be built of fire brick which does require mortaring, At the top there is a draft control, and usually at the bottom as well.

Her heater needed only branches to build a quick fast fire three times a day, although it was warm with only one firing as in the spring and fall, but in the dead of winter, it needed three. Mom's home was well insulated, and quite large, yet this stove did a great job of keeping the main thermostat inactive

I've looked at the rocket stove, and like the bench idea, but that is also possible with the Kachelofen. The latter can have fancy tile facing, or just simple mud & straw as in the Rocket stove. Those not familiar with the Kachelofen or Russian stove should give them a look.