Adding more to what I explained yesterday with regard to round fireboxes(I KNOW, I KNOW, ITS BORING BUT ESSENTIAL!!!!!!!!!!!!!!!!!!!!!)
A circular firebox/combustion chamber would also permit the better
use of a natural draft or under fire forced air combustion system-the former being less complicated simply using an aquastat controlled draft control for the combustion air path over the fire and the under fire combustion air entering the ash pit and then up through the circular combustion chamber and then to the 1,2 or 3 pass vertical fire tube sets with the first pass of pipes being upward, the second being downward and the third being upward and exiting the flue and then to the chimney.
The ash pit would be smaller because less ash is created due to the higher combustion temperatures.
This permits the boilers combustion chamber to be much smaller
and the area absorbing the heat and storing the hot water as
thermal mass very quickly.
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The exterior and interior and surface area of a right cylinder have a very large surface area which would make up the combustion chamber of an outdoor furnace or boiler.
Using three examples; a 24 inch, 36 inch and 48 inch circular combustion chambers which are made from sheets of one half inch boiler plate which are twenty four inches in width become twenty four inches tall:
We use the formula for the suface area of a right cylinder to explain it.
A 24 inch right cylinder is measured this way:
Where r equals the radius of the cylinder.
Where h equals the height of the cylinder.
The surface area of the right cylinder is explained thusly;
2*Pi* R*(r+h)
2 times 3.14 times the radius times the radius plus the height
SO in a 24 inch cylinder 24 inches tall used as a combustion chamber the exterior surface area would be explained;
2 times 3.14 times 12 times (12+24) this equals 2,712.96 square inches which is rounded off to 2,713 square inches to make it easier to deal with, which equals 18.84 square feet rounded up to 19 square feet in exterior exposed surface area to combustion.
In a 36 inch diameter cylinder 24 inches tall this becomes;
2 times 3.14 times 18 times (18+36) this equals 6,104.16 square inches rounded down to 6,104 square inches which equals 42.38889 square feet rounded down to 42 square feet in surface area.
In a fourty eight inch cylinder twenty four inches tall this becomes;
2 times 3.14 times 24 times(24+48) this equals 9,244.64 square inches which is equal to 64.199989 square inches rounded down to slight less than 64 square feet of surface area exposed to combustion.
The key to this is the smaller surface area exposed to the act of combustion being the entire interior surface and where exterior surface area of the cylinder is also radiating heat.
A boiler with a circular firebox could employ vertical fire tubes above it like the older HSTARM wood and coal boiler designs in a two or three pass configuration pulling huge amounts of heat from the fire and create huge amounts of hot water or steam in the case of coal stokers.
The circular firebox concentrates thre area of combustion just as is done when filling your firebox half full or more with firebrick to create a thermal mass in addition to the water mass in an outdoor boiler.
One could use a circular fire chamber wherein it could be raised slightly over a set of standard coal grates and welded to the support steel for the grates to create a circular combustion chamber to concentrate the heat and burn temperature to reduce smoke to a minimum and increase the efficiency of an outdoor boiler in the boiler combustion process.
Something to think about in the scheme of things when looking at the
combustion chamber of an outdoor boiler.
I would enjoy debating this issue with a manufacturer if they desire to.
A circular firebox/combustion chamber would also permit the better
use of a natural draft or under fire forced air combustion system-the former being less complicated simply using an aquastat controlled draft control for the combustion air path over the fire and the under fire combustion air entering the ash pit and then up through the circular combustion chamber and then to the 1,2 or 3 pass vertical fire tube sets with the first pass of pipes being upward, the second being downward and the third being upward and exiting the flue and then to the chimney.
The ash pit would be smaller because less ash is created due to the higher combustion temperatures.
This permits the boilers combustion chamber to be much smaller
and the area absorbing the heat and storing the hot water as
thermal mass very quickly.
==================================================
The exterior and interior and surface area of a right cylinder have a very large surface area which would make up the combustion chamber of an outdoor furnace or boiler.
Using three examples; a 24 inch, 36 inch and 48 inch circular combustion chambers which are made from sheets of one half inch boiler plate which are twenty four inches in width become twenty four inches tall:
We use the formula for the suface area of a right cylinder to explain it.
A 24 inch right cylinder is measured this way:
Where r equals the radius of the cylinder.
Where h equals the height of the cylinder.
The surface area of the right cylinder is explained thusly;
2*Pi* R*(r+h)
2 times 3.14 times the radius times the radius plus the height
SO in a 24 inch cylinder 24 inches tall used as a combustion chamber the exterior surface area would be explained;
2 times 3.14 times 12 times (12+24) this equals 2,712.96 square inches which is rounded off to 2,713 square inches to make it easier to deal with, which equals 18.84 square feet rounded up to 19 square feet in exterior exposed surface area to combustion.
In a 36 inch diameter cylinder 24 inches tall this becomes;
2 times 3.14 times 18 times (18+36) this equals 6,104.16 square inches rounded down to 6,104 square inches which equals 42.38889 square feet rounded down to 42 square feet in surface area.
In a fourty eight inch cylinder twenty four inches tall this becomes;
2 times 3.14 times 24 times(24+48) this equals 9,244.64 square inches which is equal to 64.199989 square inches rounded down to slight less than 64 square feet of surface area exposed to combustion.
The key to this is the smaller surface area exposed to the act of combustion being the entire interior surface and where exterior surface area of the cylinder is also radiating heat.
A boiler with a circular firebox could employ vertical fire tubes above it like the older HSTARM wood and coal boiler designs in a two or three pass configuration pulling huge amounts of heat from the fire and create huge amounts of hot water or steam in the case of coal stokers.
The circular firebox concentrates thre area of combustion just as is done when filling your firebox half full or more with firebrick to create a thermal mass in addition to the water mass in an outdoor boiler.
One could use a circular fire chamber wherein it could be raised slightly over a set of standard coal grates and welded to the support steel for the grates to create a circular combustion chamber to concentrate the heat and burn temperature to reduce smoke to a minimum and increase the efficiency of an outdoor boiler in the boiler combustion process.
Something to think about in the scheme of things when looking at the
combustion chamber of an outdoor boiler.
I would enjoy debating this issue with a manufacturer if they desire to.
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