The Choice of the Process for Plate Heat Exchanger Selection

Hofmann
Under normal operating conditions, the more options are symmetrical flow path plate heat exchangers, because when the volume flow of the two media fluid is roughly the same, the choice of equal arrangement is more reasonable. While the difference of the medium fluid flow on both sides is large, the small side of the fluid should choose multi-process layout. In general case, the change side of plate heat exchanger is always a single process. Multi-process plate heat exchanger, if not special needs, generally take the same number of flowways for the same liquid.
In the case of certain pressure drop, the multi-process arrangement will have a corresponding lower pressure drop for each measurement, so the flow rate will become low. In addition, multi-process layout is also an important factor of different average heat transfer temperature, which should be avoided or reduced as much as possible.

In recent years, with the diversification of plate heat exchanger application conditions, the asymmetric channel plate heat exchanger appeared in china. In foreign country people use more "hot mixing" the plate combination, that is, to allow mismatch problems among heat - flow - pressure, which also saves the heat transfer area.

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