I'm a newbie on the forum, and to rocket stoves as well. Glenn H. addressed a question re: a formula, etc. for a stove used in an aquaponics application. It triggered a couple questions in my mind since I'm trying to get my mind around the principles of rocket stoves. Does the area around the j-tube structure (pipe with insulation making up the feed tube and riser) have to be in the neighborhood of 2", or what space does that need to be in relation to the j-tube structure? Ex., if I have a 6" OD j-tube, then 2" or 3" of vermiculite, mortar, etc. around the j-tube (insulation), could I then have more than 2" between it and the outside of the barrel or whatever I come up with to use for the unit? I'm thinking more like a conventional looking wood stove, possibly larger pipe and maybe even plate welded up in the shape of a square, with the exhaust exiting at the bottom like the rocket stove typically has. The stove would be used as a heating unit in our house. I just don't want the 'mass' look of barrel, masonry couch, etc., just a stove to heat about 1200 sq. ft.
Thanks in advance for your responses, David