Michael Moreken wrote:Nice job! Dump bags of vermiculite or perlite into all open areas?
I am sure what you think Tom would achieve by filling with perlite or vermiculite. They not not add much mass and as an insulator they don't absorb much energy/heat. Also he might end up not absorbing as much heat into his mass if it is partially insulated from the hot gas. If I misunderstood your reasoning, please correct me and enlighten me. Thanks.
The outlet for the exhaust is on the floor. Filling the bottom with anything would block it:)
The entire brick bell is built on an insulated section of my slab, that heat is staying rite there.
What Tom is attempting to achieve is to maximize surface area to absorb heat. If you simply add more mass without sculpting it to increase surface area as well as providing a path to the mass so it can heat up you will simply lose heat as the new hot gas coming in from the fire, displaces the existing gas in the bell.
This is why Tom has stacks of block and brick in the bell with lots of edges sticking out into the gas stream.
It is a balancing act to get as much heat out of the gas and into the mass as possible before the gas goes out the flue and up the chimney for ever taking the latent heat with it.
Depends where I check it. External brick temps are 225+ near the core, below the barrel. Average external brick temps are running 150-175F, The barrel is 880F on top and 400-500F on the sides. Roof is 200+
What I consider to be a problem is, my mid stream exhaust is running as much as 325F at head high on the chimney. I would like to see this number around 250 F max.
My plan for this summer is to go taller with the walls and try to give it an arched domed brick roof.
Not all who wander are lost... J.R.R. Tolkien
Location: Wellington, New Zealand
posted 3 months ago
Tom, I guess it's too hot then to use water as mass storage inside the bell. What about outside near the bell?
I've always hankered after these solar tubes but never had a floor that could sustain their weight.
Location: Southern alps, on the French side of the french /italian border 5000ft high Southern alpine climate.
posted 3 months ago
thomas rubino wrote: or possably a secondary barrel bell like Max sugested.
That would be a quick fix for this winter.
You plonk a barrel above your little stub of bricks, with the tube entering it a smidge. Remove one of two lengths of that black pipe, use two elbows to move the tube to the side, from where it is now, and do a plunger tube in that barrel. Make two brick legs for the barrel, and cover it with bricks or pavers.
That's an afternoon job May be well prepared, two hours and you're done.