Thank you George, Bengi, for the excellent and thoughtful replies.
Yes, water and fire are dangerous. I have experience with live steam, boilers, and horizontal steam engines (heat engines!).
It's the kind of activity that should be kept out of the house, and enclosed in nothing more substantial than a 3-sided shed.
Applying rocket-stove tech to hot water production (or steam!) can revolutionize the practice. Thanks for the report on
the creosote non-issue. I may apply this to a mono-tube boiler for live-steam (outdoors only!) Cleaning soot and chopping
copious amounts of wood is what kills much of the fun of the live-steam hobby.
With regards my cabin project, placing the water-loop on the stove output side should keep the heat-pump aspect of the rocket design
functioning well. (The temperature delta is a little weak, but I DO want to AVOID steam.) I found another thread where Eric suggested this location as well.
Which brings me to another question:
If I replace the cob bench with a water-loop, might I turn the exhaust vertical, so my coils might be wound in progressive horizontal loops, thus avoiding any downturns/heat traps?
Then I can route straight up thru the roof (while keeping the heated side of my loop at the lowest relative position to my storage tank, improving the
Final thought: rather than taking the exhaust off at the lower OUTSIDE portion of the bell/barrel, might I plumb the exhaust thru
the top of the bell, with the hidden portion of stove-pipe passing almost to the bottom interior of the bell/barrel? (With a thermal blanket
wrapped around this hidden portion to prevent the equalization of temps.) In this way, the rocket could be made a little
Any thoughts on where to best place a water coil for a thermosiphon loop?
I'm hesitant to place it in the burn-tube, as I don't want to crash the temps, and putting a loop in the burn-tube is
difficult to design while avoiding any downturns in the plumbing to avoid heat traps or live steam. (NO ELECTRIC PUMPS!)
If a coil is placed on the outside of the drum, that seems very inefficient with the low temperature delta.
This leaves a couple options; coil hanging on the inside of drum/bell, or a coil wrapped around the Vertical Burn Chamber just
prior to insulation.
I like the later, as this will keep the Vertical Burn Chamber (made from stainless pipe) cooler, and any soot build-up will
be easier to brush free from the inside of the VBC, where one would expect it to condense, rather than having to fiddle with
scrubbing a long & unwieldy loop of copper tubing. (Monotube boilers are a bitch to clean without the aid of a steam lance.)
One-inch copper thermosiphon tube should move enough fluid to prevent steam cavitation. Thoughts?
My design will not include a cob mass bench. After the bell, it will exhaust straight up thru the roof. My cabin is two stories,
380 square feet. Stove will be located downstairs. Water loop will thermosiphon to a tank. Warm air will cycle by convective
loop thru a large grate and stairwell. TP valve near stove, mixing valve on storage tank for safety. YMMV. I'm located in
the NW USA.