About high fin tube heat exchanger design

[Carol3377]

Dear all,
I am now trying to design an effective heat exchanger used for heat recovery from high temperature gas(higher than 450 C).
The gas is supposed to flow outside the finned tubes. However, the Aspen Exchanger Design & Rating software seems only be able to design low fin tubes, with fin height lower than 1.5mm.
So I wonder if it is not possible to design high fin tube & shell heat exchanger using commercial software like Aspen EDR or HTRI?

Thank you.

 

[EdStainless]

For most of these you need the correlation factors from the manufacture of the tubes.
The factors for most finned tubes are empirical.
Are these wrapped fins or welded?

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P.E. Metallurgy, Plymouth Tube

 

[Carol3377]

Thank you for your response.

Details not determined yet. I see what you mean. But my puzzle is, I used commercial software to do the primary design and I guess most factors in the software for low-fin tubes are empirical (rather than numerical solutions), but why don't they have factors for high fins? It seems that only specific air-cooled heat exchangers have different fin options. But what about the non-air-cooled heat exchangers? If they cannot deal with high fins, does it mean that the only way is to find proper correlation factors and do my own design programming?

 

[EdStainless]

There are a lot of different proprietary fin configurations.
Each of the companies publishes their own factors.
The low fin world is fairly standardized by comparison.


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P.E. Metallurgy, Plymouth Tube

 

[Christine74]

High-fin tubes aren't really amenable to shell-and-tube heat exchangers because they can't support both longitudinal flow and crossflow. If you used circumferential fins you would have high pressure drop and poor heat transfer in the window area, and if you used longitudinal fins you'd have poor heat transfer and high pressure drop in the crossflow area. Furthermore I don't know how you'd support the tubes, as conventional baffles are not an option.

-Christine

 

[Carol3377]

Thank you very much.
The low fin is not satisfactorily effective especially on the gas side (shell side). I will try to find the high fin factors and use them to do the calculation and comparison. I will do the pressure drop too to see if its too high for requirement. Thank you again.