How do you calculate heat flux through a piece of metal?

AI Thread Summary
To calculate heat flux through a cylindrical steel bar, the thermal conductivity of the steel is essential. The heat flux (q) can be determined using Fourier's Law, which states that q equals the negative thermal conductivity (k) multiplied by the temperature gradient (dT/dx). In this case, the temperature difference between the heated end (31°C) and the cooler end (28°C) is divided by the length of the bar (12mm). This calculation will yield the heat flux in watts per square meter (W/m²). Understanding these principles allows for accurate heat flux calculations in metal objects.
Con?used
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How do you calculate heat flux through a piece of metal??

Hello,
I need to calculate heat flux in W/m2 through a small cylindrical steel bar measuring 12mm length x 2mm diameter. At one end of the bar the temperature is 31C (the heated side) and at the other end it's 28C.

How do I calculate the heat flux in the above scenario? Is it possible? I'm guessing that I need to know the thermal conductivity of the steel at least?

Any assistance would be much appreciated.
Many Thanks
 
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Hi Con?used, welcome to PF!

You do indeed need to know the thermal conductivity. The heat flux q is given by Fourier's Law:

q=-k\frac{dT}{dx}=-k\frac{T_2-T_1}{\Delta x}

where k is the thermal conductivity. Does this answer your question?
 


Thanks Mapes
 
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