The pinching and narrow point problem
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This post was last edited by What is this of mine? on 2021-10-18 09:55. I would like to ask fellow experts: are the concepts of pinch points and narrow points the same in heat exchanger network optimization? I understand that the temperature difference at the pinch point is the narrowest value; I’m not sure if that’s correct. I think a pinch point is simply a temperature point – there is a pinch point for the heat flow and another for the cold flow. The temperature difference for heat transfer between these two pinch points is the smallest, and this difference is what constitutes the narrow point. Cold utility systems cannot be used above the pinch temperature of the hot and cold streams, and hot utility systems cannot be used below that pinch temperature; otherwise, it constitutes a waste of energy. I’m not sure if I understand correctly
Since you know what a pinch point is and what a narrow point is. Why is it still considered the same concept?
I’m not sure if my understanding is correct. I have another question: there should be no cold utility systems above the pinch point, and no hot utility systems below it; heat transfer through the pinch point is also not allowed. How should this be understood?
You understand it perfectly well. The use of pinch technology is aimed at saving energy; there is no such thing as \"heat transfer through the pinch points,\" and we always strive to save energy.
Oh, thank you. I’ll check out some relevant materials to learn more.**