What is the general overall heat transfer coefficient of flue gas to water?
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I got 65, but the calculation gave around 55; I’m not sure if that’s correct
For Yan Qi, radiation-conducted heat transfer and convection heat transfer are the main mechanisms; a value of around 50 is sufficient.
For Yan Qi, radiation-conducted heat transfer and convection heat transfer are the main mechanisms; a value of around 50 is sufficient.
Reply to 3# ljc. . . There’s also radiation. It seems that most books on heat exchangers don’t mention this. How is this calculated? Funk:
Yes. . . It’s probably around this figure: 40–70
It can be calculated using the formulas in the heat exchanger calculation manual. It’s probably between 40 and 70, depending on the flue gas velocity.
For radiation heat transfer, please refer to the book on principles of chemical engineering and chemical equipment design, “Waste Heat Boilers”.
I’m frustrated; I calculated that the heat exchange area is over 170, but the engineers say it’s too large
Is there anyone knowledgeable who can provide a proper answer to this question? I’ve recently been working on heat exchanger designs in this area, using heat pipes to enable indirect heat exchange between flue gas and water. For the design calculations, it’s necessary to determine the heat exchange area; beginners can find this a bit confusing
If it is a finned tube, 20 is quite high； If it is a light tube, 50-70 is normal. It depends on the flue gas velocity, tube diameter, type of fuel, etc.
What material does this correspond to, 50-70?