I recently had an idea, and I wonder how effective it would be. Yes, it's a barrel stove, but I would be using it in my shop, which is a steel building reinforced by cinderblocks and a thick concrete floor (very little fire risk). I've attached a couple sketches I did on the idea, and I want to get some opinions.
Basically, it's a standard double barrel setup. I've seen guys that have welded a baffle plate a few inches from the top of the the bottom barrel and run secondaries right underneath that, like you would see with a modern EPA stove. My design has the both secondary inlets at the back of the stove on the bottom barrel (one for each side of the firebox) that run about 3/4 the way to the door in the front. They are connected a 90 degree pipe elbow to a curved section of pipe running upwards to stay in contour with the inner wall of the barrel, then through another 90 degree elbow back into straight pipes that then run back to, and up, the chimney. I would use 8 inch steel pipe for the flue connecting the barrels to allow room for the secondary tubes to run inside and up to a few inches below the circulator baffle in the upper barrel,without creating a narrow choke point in the bottom flue pipe. My ultimate aim here is to give the air in the secondaries a long passage through the firebox, ensuring maximum heat transfer to the air. This is also why I run the tubes inside of the flue, to minimize heat loss in the superheated air going through them, as I want the secondary burn to happen in the upper barrel.
I've researched barrel stoves for years now, but I've never seen one with the secondary reaction exclusively in the upper barrel. I may run 3 or 4 pipes thru the upper barrel above the circulation baffle that I could hook a small blower up to, as many people have done. How well would this work?
![[Hearth.com] Secondary combustion in a double barrel stove?](https://www.hearth.com/talk/data/attachments/240/240141-86d1cdb5f0f8185a6615f70d04b8a8a4.jpg?hash=w52EZ690XQ "[Hearth.com] Secondary combustion in a double barrel stove?")
![[Hearth.com] Secondary combustion in a double barrel stove?](https://www.hearth.com/talk/data/attachments/240/240142-1e91dd92e6ae4160d23d2ab3f43cacba.jpg?hash=1SMuDusLfp "[Hearth.com] Secondary combustion in a double barrel stove?")
Basically, it's a standard double barrel setup. I've seen guys that have welded a baffle plate a few inches from the top of the the bottom barrel and run secondaries right underneath that, like you would see with a modern EPA stove. My design has the both secondary inlets at the back of the stove on the bottom barrel (one for each side of the firebox) that run about 3/4 the way to the door in the front. They are connected a 90 degree pipe elbow to a curved section of pipe running upwards to stay in contour with the inner wall of the barrel, then through another 90 degree elbow back into straight pipes that then run back to, and up, the chimney. I would use 8 inch steel pipe for the flue connecting the barrels to allow room for the secondary tubes to run inside and up to a few inches below the circulator baffle in the upper barrel,without creating a narrow choke point in the bottom flue pipe. My ultimate aim here is to give the air in the secondaries a long passage through the firebox, ensuring maximum heat transfer to the air. This is also why I run the tubes inside of the flue, to minimize heat loss in the superheated air going through them, as I want the secondary burn to happen in the upper barrel.
I've researched barrel stoves for years now, but I've never seen one with the secondary reaction exclusively in the upper barrel. I may run 3 or 4 pipes thru the upper barrel above the circulation baffle that I could hook a small blower up to, as many people have done. How well would this work?
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