How can one determine if there are any unreasonable aspects in HTRI’s final report? What are the basic rules?
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How can one determine if there are any unreasonable aspects in HTRI’s final report? What are the basic rules?
From the calculation sheet, it doesn’t seem to be a serious issue; there are mainly two problems: one is that the spacing between the baffle plates is a bit large, resulting in too low a flow velocity in the shell side. Second, the margin is a bit small. The small device htri is not particularly accurate; it’s better to have a larger margin.
Anything else? Dear experts, please share your insights – what are the basic rules or requirements that need to be met?
Look at the WARNING. According to the calculation, the flow velocity on the shell side is too low while that on the tube side is too high, which is unreasonable
Which parameters can be changed to make it so?
Your question is quite broad; change the way the medium flows. The gas flow rate in the shell side should be 3–15, while that in the tube side should be 1.5–3
If I can’t change it, are there any other ways to make a change?
The shell diameter is reduced, the tube length is increased, and the spacing between the baffle plates is adjusted. The person upstairs explained it quite clearly: for heat exchangers with a small diameter, the HTRI calculation is not very accurate
I think aside from the slightly small margin, there are no other issues – the baffle spacing or the size of the gaps can be adjusted to ensure that the flow velocities between the baffles and at those gaps are roughly the same. As for high flow velocities, as long as the pressure drop remains within acceptable limits and the B-flow data is appropriate, that’s fine.
1. There is a contradiction between the calculated pressure drop and the allowable pressure. 2. The gap in the baffle plates is usually 25%~45%. 3. The spacing between baffle plates is 0.3~0.6Di, which seems a bit large. 4. The heat exchange margin is generally 10~15%, with some cases reaching 15~20%. 5. The flow rate in the shell side is a bit low. 6. Generally, water should flow in the tube side; it is recommended that water be used in the tube side while gas is used in the shell side.