Tiny Rocket Heater, thoughts

I have a concept in my head for a tiny Rocket, maybe mass, heater.  I'm thinking desktop sized, something that could raise the temperature of a 10' sq. x 8' room 10 deg. F.  What do you think, doable?

I'm thinking the barrel would be about the size of a 24oz beer can and it would eat tree trimmings no larger than a nickle in diameter.

I have built a Rocket stove/ heater in my back yard as a proof of concept to myself.  It worked ok, but I did learn why you must use firebricks.  Standard bricks/ cmu just do not hold up to fire.  No worries over spilled milk though, it was just something fun to do on a day off.

Dave Brownson wrote:
I have a concept in my head for a tiny Rocket, maybe mass, heater.  I'm thinking desktop sized, something that could raise the temperature of a 10' sq. x 8' room 10 deg. F.  What do you think, doable?

Depends on insulation and air tightness of the room. Not sure I want to live in a room that tight

I'm thinking the barrel would be about the size of a 24oz beer can and it would eat tree trimmings no larger than a nickle in diameter.

Barrel? or riser? I have an idea for a RMH with a riser that size.... but no barrel. And probably taller. I was thinking of using tin for the mass at least right after the riser while I have enough heat to melt tin. Then brick or caste iron farther up. Once the inside of the riser gets really small, its ability to push the exhaust down again is diminished. Something to do with the friction of the flue gas in close proximity to the riser walls. This is one of those experimental areas. No one has tried a lot of these smaller things... give it a go and tell us how it goes.

Tin cans are a good idea.  One that I hadn't visited yet.  I was sure that an aluminum one would melt though, particularly at the top of the riser, but I did like the shape that the bottom of an aluminum can makes.  I thought the inverted dome would be a good shape for the top of the barrel.

Dave Brownson wrote:
Tin cans are a good idea.  One that I hadn't visited yet.  I was sure that an aluminum one would melt though, particularly at the top of the riser, but I did like the shape that the bottom of an aluminum can makes.  I thought the inverted dome would be a good shape for the top of the barrel.

I wasn't thinking of tin cans... although the size might be good. Tin cans are now just steel and use a plastic coating on the inside instead of tin. My thought was to have a round steel tank with the flue going up the centre... and filling the tank with tin. I would then insulate the outside so that when the tank was at the melt point of tin and higher, the insulation would let just enough heat through for the outside temp to be 150F or so. This way, a small amount of mass could do the work of a lot more brick. As the tin cooled, it would get to it's freeze point and the heat released for phase change would happen over a longer time at that temp. This has been used in solar cookers for after dark cooking.

Have you seen this one? It's pretty small:

swskies wrote:
Have you seen this one? It's pretty small:

http://www.youtube.com/watch?v=P6ValmUnjz4&feature=related

Some of the ideas could be used. That is a rocket cook stove and what we are looking at a heater with an exhaust that goes outside. What I have heard of these tin can ones is that they have a short life span... 6months to a year and a half depending on amount of use before the cans rot out. That is the size we are talking about though.