Thermal Numeracy: Difference between revisions

Latest revision as of 01:31, 1 December 2015

Thermal numeracy refers to understanding the quantities of heat produced, emitted, and transferred in various physical phenomena.

BTU - 1 lb water raise by 1 degree F
BTU of wood is 8k-9k per lb -[1]
U value of insulation is BTU/(hr*sq ft*deg F). It is the inverse of R value - [2]
Fireplace heat loss from chimney can be 80-90% - [3]
At high temperatures, temperature in degrees F is about 2x that of degrees C. Specifically, ~9/5 times.
Glenwood 5000 stove is rated for 100k BTU, with 11 sf of heat exchange area - about 10k BTU/SF
1 kW ~ 3000 BTU/hr
Black pipe is only $12/square foot (10k BTU) of heat exchange area using 1" pipe! - [4]
1/2" PEX power production - 22 BTU/hr for 1 foot of length - [5]. 500 feet per trough = 11k BTU
Cord of wood is $235, and 4000 lb - [6]
Thermal expansion coefficient of water is 1/10000 for F - [7]

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 *Black pipe is only $12/square foot (10k BTU) of heat exchange area using 1" pipe! - [https://docs.google.com/presentation/d/1xTUzDwmhszU4VwrCzDTLW_LENnYHIbPXisFgCwlOvg4/edit#slide=id.g6773fc365_0_0]
 *1/2" PEX power production - 22 BTU/hr for 1 foot of length - [http://www.pexuniverse.com/content/pex-tubing-sizes-floor-output]. 500 feet per trough = 11k BTU
-*Cord of wood is $235, and 4000 lb.
+*Cord of wood is $235, and 4000 lb - [https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8&client=ubuntu#q=how%20much%20does%20a%20cord%20of%20wood%20cost]
+*Thermal expansion coefficient of water is 1/10000 for F - [http://www.engineeringtoolbox.com/cubical-expansion-coefficients-d_1262.html]