btus of 2 in black iron pipe

ed wallace

anyone know how many btus per foot of 2 in black iron pipe with and with out fins when used in a hot water system

Mark Eatherton

I don't know about the fins....

But 2" pipe should be relatively easy to calculate based on EDR.



2 X Pi X Radius = circumfrence.



2 X 3.14 = 6.28



6.28 X 1 (2" diameter, 1" radius) then each inch of 2" pipe has 6.28 square inches of surface.



144 (square inches in a square foot) divided by 6.28 = 22.9 linear inches per square foot of EDR. So roughly, every 2 feet of pipe equals one square foot of radiation. You will have to determine the fluid temp inside to see what it will put out.



Come to think of it, in al my years, I've never seen 2" finned steel tube. 1-1/4" copper is the biggest I've seen. But that is not to say that I have seen everything, just most everything ;-)





ME

Jamie Hall

and to Mark's

surface area of the pipe, the fins aren't that hard either -- each fin has an effective area of the area of the fin, minus the area of the pipe to which it is attached, doubled (since both sides radiate).  So if, for instance, your fins are 4" square, the area of the fin is 16 square inches, minus the area cut out for the pipe -- 6 square inches, more or less, so 10 square inches per side.  So 20 square inches per fin, divided by 144 square inches per square foot -- call it .14 square feet per fin.



Then count up the number of fins per foot and multiply, add that to the area of the pipe per foot, and there you go...

JeauxBleaux

Some Canucks already did this for us.

I found this when searching heating methods for layer hen houses.



"Water temperatures of 93 to 98°C (200 to 208°F) produce

approximately 200 watts/m (200 BTU/ft) of 2" black iron pipe

and about 500 watts/m (500 BTU/ft) of 2" finned pipe. The pipes

are placed in front and below the incoming fresh air inlets in

negative pressure and naturally ventilated barns."



http://www.cps.gov.on.ca/english/plans/E5000/5210/M-5210L.pdf