Monitor building inner defect with inverse heat transfer

AI Thread Summary
The discussion focuses on determining the presence of inner defects, such as air pockets, in a wall through heat transfer analysis. It establishes a baseline scenario where a wall without defects exhibits specific temperature readings and thermal capacitance. When assessing a wall with a potential air pocket, the thermal capacitance value is expected to be higher, indicating reduced heat transfer due to air's lower thermal conductivity. The participants note that using heat transfer rates to detect such defects may be less effective compared to alternative methods. Overall, the effectiveness of heat transfer analysis for defect detection is questioned, suggesting that other techniques might yield better results.
songyang
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Assume that there is a original wall which does not have any defect inside. After an excitation of heat at one side of the wall, Ti is 37°C and To is 30° C. Thermal capacitance is assume 1. So the heat transfer is 7.

For another condition, i want to find out if the wall has air pocket inside or not. The same procedure goes on with an excitation of heat at one side of the wall until it reach the same Ti and To as above. We know that air pocket has its own thermal capacitance, so the value of K must be greater than the original condition. My question is, how am I suppose to know if the wall has inner defect or not based on the condition as given above.

If guessing the value of heat transfer to find the combined thermal capacitance, is it applicable?
 
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songyang said:
Assume that there is a original wall which does not have any defect inside. After an excitation of heat at one side of the wall, Ti is 37°C and To is 30° C. Thermal capacitance is assume 1. So the heat transfer is 7.

For another condition, i want to find out if the wall has air pocket inside or not. The same procedure goes on with an excitation of heat at one side of the wall until it reach the same Ti and To as above. We know that air pocket has its own thermal capacitance, so the value of K must be greater than the original condition. My question is, how am I suppose to know if the wall has inner defect or not based on the condition as given above.

If guessing the value of heat transfer to find the combined thermal capacitance, is it applicable?
Actually, the rate of heat transfer would be less with an air pocket, since air has a lower thermal conductivity. Detecting a pocket using heat transfer would be less sensitive than other methods.
 
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