mass stove; looking firebrick and experiences

[clasou]

Hello middle-middle.
If you want feedback, go to futura science in the forum house, there are wires on the mass stoves and their return, moreover they are so to speak only of auto builders.
a + claude

[dedeleco]

A few orders of magnitude to locate:
A ton of brick, earth, clay, stone, it is approximately between 10 to 30KWh of stored with T from 20 ° c to 56 ° C (10KWh), or to 92 ° C (20KWh) or to 128 ° C (30KWh / ton), or 3kg, 6Kg or 9Kg of burnt wood !!!

We can reduce the weight by storing in paraffin which make around 50 to 60 ° C and which stores 220KJ / kilo by melting more a thermal capacity double that of the brick which gives for 92 ° C (delta T from 20 to 92 ° C = 2x36 ° C) 40KWh / ton in thermal and molten capacity 61KWh / ton or in total with paraffin at 92 ° C a capacity of 40 + 61 = 101KWh / ton instead of 20KWh with usual brick or stone, or 5 times more stock for the same weight.

So with paraffin to store the same heat, the weight is divided approximately by 5, and therefore 200Kilos of paraffin mass pan is equivalent to the classic 1 ton, for a price of € 1000 to 2000 per tonne of paraffin and as much for paraffin tanks and exchangers, paying attention to the expansion of the paraffin (10%) and other surprises such as leaks.

So a mass stove can be lightened by a factor of 5 with paraffin, !!
http://en.wikipedia.org/wiki/Paraffin
http://en.wikipedia.org/wiki/Heat_capacity
http://www.collectionscanada.gc.ca/obj/ ... q21839.pdf

Finally, it is necessary to take into account the thermal diffusion time, around mm2 / s, i.e. for 10cm approximately 100x100 = 10000s = 2,7h and therefore during rapid outbreaks, it is necessary to heat the internal mass of the stove that it is everywhere less than 5cm (or 2500s time) of hot fumes or conductive metals !!!
To restore the heat over a longer time, we can be 20cm from the outside air (40000s)

http://fr.wikipedia.org/wiki/Diffusivit%C3%A9_thermique
http://de.wikipedia.org/wiki/Temperatur ... %A4higkeit

[rpsantina]

I do not know why but I do not feel the blow of the paraffin.




But actually, it's tempting.

[dedeleco]

Nice illustration !!!

[clasou]

Hello,
Certainly paraffin, is a good accumulator, but I think it is not at all suitable for the mass stove.
In theory the amount of heat stored could be the same, but I think in practice there will be a big difference.
You only have to look at the section of a stove, the ducts that capture the calories from the smoke, the exchange surface to see that there is little chance of being beneficial.

After perhaps that starting from a closed hearth on which one would make a sarcophagus with batteries with paraffin coated with a layer of refractory brick would be perhaps more manageable.

We will avoid sweeping problems being independent of the home,
Is when it smells 150 or 200 degrees and loses such quality?
a + claude

[dedeleco]

It is a way to have a much lower weight and everything is in the well designed exchangers, very rudimentary with brick, but more elaborate with metal containers for paraffin, gaseous expansion vessel removing odors (nothing comes out) and a not too high temperature of the paraffin (130 ° C max) which absorbs the heat will not overheat.
Often the mass stove can not be used because too heavy for the floor not strong enough and therefore 200Kg instead of a ton is very interesting, but paraffin is used a bit like a water exchanger in closed containers heated by bars or metal plates which bring heat without overheating.
We must therefore think very differently from bricks in smoke.

[clasou]

Yes, I understand the weight problem.
If you have photos (cut) or links on the plans that would interest me.
But what is the basis of the heart.
if not for justmilieu here are pictures of a self-builder

https://picasaweb.google.com/1127801815 ... PETnVrqH3w

Good, the machine apparently weighs 5 tonnes.
a + claude