Heat transfer from a fluid linear?

AI Thread Summary
The discussion centers on whether the BTU output from a heat exchanger is the same when cooling water from 180 to 160 degrees as when cooling it from 100 to 80 degrees, both representing a delta T of 20 degrees. It is noted that if the temperature change occurs at constant volume and the effect of temperature on heat capacity is ignored, the heat output would be equivalent. However, heat capacity does vary slightly with temperature, which could affect the results. Participants emphasize the importance of checking the heat capacity variation over the specific temperature range. Overall, the relationship between temperature change and heat transfer is not strictly linear due to these factors.
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If I had water at 180 degrees and dropped the temperature to 160 degrees over a heat exchanger, would I have the same BTU output as if I had water at 100 degrees and dropped the temp to 80 degrees? Delta T is 20 degrees for both situations.

I know if we were talking about Ke related to mass and velocity, and changed the velocity, energy would not trend in a linear fashion. Not sure about heat energy in water though.

Thanks
 
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If the temperature change is carried out at constant volume, neglecting the effect of temperature on heat capacity, the amount of heat would be the same. The heat capacity does vary a little with temperature, but typically not much. You need to check how much the heat capacity varies over the temperature range of interest.
 
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