Q2-4 Flow Maldistribution in Plate Heat Exchangers
Three types of flow maldistribution occur in plate heat exchangers:
- channel flow maldistribution
- port flow maldistribution
- flow maldistribution occurring when different plate groups are arranged in a given pass
Channel flow maldistribution, which occurs because channels are asymmetrical with respect to the inlet and outlet ports, is represented by diagonal or, more likely, parallel flow. Proper design of a plate’s inlet and outlet flow distribution regions minimizes this problem.
Port pressure variation causes the flow rate to differ between channels, creating port flow maldistribution. The third type of flow maldistribution occurs because unequal hydraulic resistance exists between two different plate groups in one pass. Fluid more easily passes through the plate group having the higher chevron angle, due to the group’s lower hydraulic resistance.