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Conduction heat flux calculator

For fixed thickness, equation 13-1 says heat flux is proportional to K and temperature difference.

Units
q=K×ΔTdq = \frac{K \times \Delta T}{d}

Calculator

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Btu·in/(h·ft²·°F)
°F
in
Btu/(h·ft²)

Worked example

Given

  • KK = 0.32 Btu·in/(h·ft²·°F)
  • ΔT\Delta T = 90 °F
  • dd = 2.5 in
q=0.32×902.5=11.52q = \frac{0.32 \times 90}{2.5} = 11.52

Symbols and units

SymbolMeaningUnit
qqheat flow per surface areaBtu/(h·ft²)
KKthermal conductivityBtu·in/(h·ft²·°F)
ΔT\Delta Ttemperature difference°F
ddmaterial thicknessin

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Results are estimates for study and screening. Check the inputs, units and assumptions before you use them for design, billing or contract decisions.