How can units of heat ever be ft^3/s?

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The discussion centers on the confusion between volumetric throughput rate (Q) and heat transfer rate (dQ/dt) in a specific problem. Participants clarify that Q represents volumetric flow, not heat, despite the problem referencing dQ/dt as the heat transfer rate. There is speculation about whether the same letter usage for both concepts stems from historical theories or simply a lack of alternative symbols. The conversation highlights the importance of distinguishing between these terms to avoid conflating them. Understanding this distinction is crucial for accurately solving the problem at hand.
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Homework Statement
I have a fluid mechanics textbook by Frank White which includes an example problem about a steady flow machine with one inlet and two outlets. The details of the actual problem are actually not so important as the follow: given information includes the areas of the inlets, the heat, the temperature, the pressure, and a height z. Included next to each given quantity is the unit in which its given. Next to heat, the unit is shown as (ft^3/s) where ft is feet and s is seconds. This is confusing me a bit. How can energy have those units? He subsequently even finds the fluid velocity at the inlets by dividing the heat by the inlet area, showing the units were not mistakenly typed. I am rather frustrated. Would anybody be able to explain how energy units would be length cubed over time?
Relevant Equations
Q (ft^3/s), A (ft^2), V (ft/s) => V = Q/A??? Where do the heat units come from??
Please and thank you!
 
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Q is the volumetric throughput rate, not heat.
 
Chestermiller said:
Q is the volumetric throughput rate, not heat.
Hello, thank you for your response. He does however explicitly refer to dQ/dt as the heat transfer rate in the very same problem. (it is in fact dQ/dt that we are set to find in the problem). Could it be that he is simply equating the volumetric through rate with the heat?
 
Chestermiller said:
Q is the volumetric throughput rate, not heat.
Does the use of that same letter for heat flow come from the theory of caloric fluid or did we just run out of alphabet to use?
 
craveneye13 said:
Hello, thank you for your response. He does however explicitly refer to dQ/dt as the heat transfer rate in the very same problem. (it is in fact dQ/dt that we are set to find in the problem). Could it be that he is simply equating the volumetric through rate with the heat?
Or I wonder if it is just an unfortunate use of the same letter ha
 
hutchphd said:
Does the use of that same letter for heat flow come from the theory of caloric fluid or did we just run out of alphabet to use?
I am beginning to suspect the latter, and I just conflated the two. Thank you for your help!
 
craveneye13 said:
Hello, thank you for your response. He does however explicitly refer to dQ/dt as the heat transfer rate in the very same problem. (it is in fact dQ/dt that we are set to find in the problem). Could it be that he is simply equating the volumetric through rate with the heat?
What is the exact word-for-word statement of the problem?
 
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