InFinding heat transfer coefficient experimentally

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The discussion focuses on experimentally determining the heat transfer coefficient (h) for a cubic box by measuring the heat transfer rate (Q). The method involves placing thermocouples on the box's exterior and an object inside to monitor temperature changes over time. The user considers using the temperature difference divided by time to calculate Q, while treating the space between as a single resistance. Newton's law of cooling is suggested as a potential approach for this calculation. The user expresses concerns about the cost of heat flux sensors, indicating a preference for simpler methods.
DinoRF
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I'm working on a project where I have to construct a cubic box, then find the heat transfer coefficient through the box. I will be placing various object in the box to run tests on how they change the eat transfer coefficient. If I want to use the equation: Q=h*A*delta-T, how do I find Q, the heat transfer rate?

I'm thinking I will have thermocouples on the outside surface and on object on the inside of the box. I'll treat all the space in between as a single resistance, since I'm not worried about the heat transfer coefficient with respect to convection, radiation, or conduction, but rather the overall coefficient.

If I got the data for the outside temperature and the inside temperature and plotted that vs. time, would the Q just be the difference divided by the time of that difference?

Once I get Q, then solving for h should be simple.

I've also seen heat flux sensors, but those are expensive and I think and hope they are unnecessary.

-Matt
 
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You might be able to use Newton's law of cooling.
 
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