Understanding Average Specific Heats in Fluid Mechanics Fundamentals

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Average specific heats are used in fluid mechanics because specific heat values can vary with temperature, leading to the need for an average over a range. Different materials exhibit different specific heat values, which necessitates averaging for accurate calculations. Measuring specific heats can be complex, often requiring precise experimental methods, such as those demonstrated in Joule's experiments. Understanding these concepts is crucial for applying thermodynamic principles effectively. The discussion highlights the importance of recognizing temperature dependence in specific heat measurements.
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I have been refreshing my fundamentals. Average specific heats are confusing for me. Why they are average? Are there different values for them so the averages are taken? Would you please explain this?

Source: Fluid Mechanics Fundamentals and Applications by Çengel/Boles.
Thank you.
 
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Sure, many materials have specific heat values that change with temperature. The one above is for diamond.
 
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How can scientists measure these values? I think it should be very hard process.

Thank you.
 
mech-eng said:
How can scientists measure these values? I think it should be very hard process.

Thank you.
Read about Joule's experiments.
 
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