Thermodynamics question: temperature between layers

AI Thread Summary
The discussion centers on calculating the outside temperature of feathers in a thermodynamic context, given an air temperature of -15 degrees. The user has successfully calculated the total heat transfer coefficient but is unsure how to proceed to find the temperature between layers. Clarifications are sought regarding the thermal "circuit" and the concept of a "third layer," which is identified as the surface of the feathers. Suggestions include sketching the thermal circuit and researching the surface heat transfer coefficient for better understanding. The conversation emphasizes the importance of visualizing thermal resistance and temperature points in solving the problem.
Adam Rabe
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Homework Statement



penguin heat loss question.PNG


Homework Equations


h = k/d
1/h (total) = 1/h + 1/h + 1/h... + 1/h (surf)
Q/t = h A T

The Attempt at a Solution


For the thermodynamic one i got up to calculating the total heat transfer coeffecient but i don't know where to go from there as its asking for the outside temperature of the feathers, whilst giving an air temperature (-15 degrees).

Help would be greatly appreciated ~ Adam
 
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Could you sketch the thermal "circuit" showing the temperature points and thermal resistance between each? Think ratios or "potential divider" if familiar with electronics.
 
CWatters said:
Could you sketch the thermal "circuit" showing the temperature points and thermal resistance between each? Think ratios or "potential divider" if familiar with electronics.
Hello i tried sketching the circuit but i just can't seem to get it. Is there some sort of 3rd layer between the feathers and air? If so how would i go about finding the temperature of it? Also I am not familiar with potential dividers
 
Look up "surface heat transfer coefficient". The "third layer" as you called it is the surface of the feathers.
 
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